WO2016035458A1 - Process and device for producing nanofiber, and process for producing nonwoven fabric - Google Patents

Process and device for producing nanofiber, and process for producing nonwoven fabric Download PDF

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Publication number
WO2016035458A1
WO2016035458A1 PCT/JP2015/070371 JP2015070371W WO2016035458A1 WO 2016035458 A1 WO2016035458 A1 WO 2016035458A1 JP 2015070371 W JP2015070371 W JP 2015070371W WO 2016035458 A1 WO2016035458 A1 WO 2016035458A1
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WIPO (PCT)
Prior art keywords
solution
nozzle
liquid
tip
nanofiber
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PCT/JP2015/070371
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French (fr)
Japanese (ja)
Inventor
小倉　徹
片井　幸祐
新井　利直
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富士フイルム株式会社
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Publication of WO2016035458A1 publication Critical patent/WO2016035458A1/en

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    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D5/00—Formation of filaments, threads, or the like
    • D01D5/04—Dry spinning methods
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
    • D01F2/24—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives
    • D01F2/28—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives from organic cellulose esters or ethers, e.g. cellulose acetate
    • D01F2/30—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives from organic cellulose esters or ethers, e.g. cellulose acetate by the dry spinning process
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
    • D04H1/425—Cellulose series
    • D04H1/4258—Regenerated cellulose series
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
    • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
    • D04H1/728—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged by electro-spinning

Definitions

  • the present invention relates to a nanofiber manufacturing method and apparatus, and a nonwoven fabric manufacturing method.
  • fibers having a nano-order diameter of several nm or more and less than 1000 nm are used as materials for products such as biofilters, sensors, fuel cell electrode materials, precision filters, electronic paper, etc. Development of applications in various fields is actively conducted.
  • the electrospinning method is performed using an electrospinning device (electrospinning device) having a nozzle, a collector, and a power source (see Patent Document 1). A voltage is applied between the nozzle and the collector by the power source, and for example, the nozzle is negatively charged and the collector is positively charged.
  • a conical protrusion composed of the solution is formed at the opening at the tip of the nozzle (hereinafter referred to as the tip opening).
  • This conical protrusion is called a Taylor cone.
  • the applied voltage is gradually increased and the Coulomb force exceeds the surface tension of the solution, the solution extends from the tip of the Taylor cone and a spinning jet is formed.
  • the spinning jet moves to the collector by Coulomb force and is collected as nanofibers on the collector.
  • the solution When using a solvent that easily evaporates (for example, a highly volatile solvent) for the solution sent from the nozzle, the solution may solidify and clog at the opening of the tip. Moreover, when the solution solidified to some extent moves away from the opening of the tip, the solidified solution may fall on the collecting surface of the nanofibers collected on the collector. Thus, the clogging or solidification of the solution makes it impossible to reduce the quality of the product or to use it as a product. For this reason, in Patent Document 2, the cleaning means is used to remove the solidified solution by bringing the flexible member into contact with the tip opening, or to remove the solidified solution by sucking the tip opening.
  • a solvent that easily evaporates for example, a highly volatile solvent
  • an air spraying portion is provided at a position separated from the nozzle tip opening by a predetermined distance, and air is sprayed by the air spraying portion in the traveling direction of the spinning jet to promote the movement of the spinning jet to the collector. Increasing fiber production.
  • a Taylor cone is stably formed, and the spinning jet and the flying of the fiber are also stabilized.
  • a solution in which the solvent easily evaporates for example, a solution having a high solvent evaporation rate
  • a Taylor cone cannot be formed, and even if it is formed, the solvent on the surface of the solution extruded from the nozzle evaporates quickly. By doing so, a liquid ball may be generated.
  • the liquid ball has a substantially spherical shape instead of a substantially conical shape like a Taylor cone, and the surface is increased in viscosity by evaporation of the solvent to form a skin, and the inside remains as a solution having a high solvent concentration.
  • liquid balls When liquid balls are generated, it becomes difficult to blow out the solution from the surface even if there is sufficient charge, and even if the spinning jet is ejected, the flight is discontinuous and the nanofiber has a uniform thickness. It becomes difficult to form.
  • the liquid ball may drop due to the vibration of the apparatus, etc., and sticks to the nanofiber accumulated on the collector in the form of a non-woven fabric and becomes a defect.
  • the integrated nanofiber may become unusable as a product, or the quality as, for example, a nonwoven fabric may deteriorate.
  • An object of this invention is to provide the nanofiber manufacturing method and apparatus which can maintain a Taylor cone stably, and can manufacture a nanofiber stably, and a nonwoven fabric manufacturing method in view of the said problem.
  • a cellulosic polymer is dissolved in a solvent, a solution charged in a first polarity is taken out from the nozzle, and the same substance as the solvent component is included at the tip from which the solution of the nozzle comes out.
  • a liquid having a lower concentration of the cellulosic polymer than the solution is supplied at a flow rate in a volume within the range of 5% to 20% of the solution, and the periphery of the solution from the tip is covered with the liquid. It is characterized by attracting the solution from the nozzle and collecting it as nanofibers by means of a collector charged to a second polarity opposite to the polarity.
  • the liquid it is preferable to supply the liquid by discharging the liquid from between the nozzle and a liquid feeding pipe arranged concentrically with the nozzle with a gap around the nozzle. It is preferable that the tip from which the liquid in the liquid feeding tube protrudes protrudes from the tip of the nozzle.
  • the cellulose polymer is preferably at least one of cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, nitrocellulose, ethylcellulose, and carboxymethylethylcellulose.
  • the nanofiber production apparatus of the present invention includes a nozzle for dispensing a solution in which a cellulosic polymer is dissolved in a solvent, and a liquid containing a substance that is the same as the solvent component at the tip of the nozzle solution and having a lower concentration of the cellulosic polymer than the solution.
  • the apparatus includes a collector that collects as a fiber, and a voltage application unit that charges the solution and the collector with opposite polarities by applying a voltage to the solution and the collector that come out of the nozzle.
  • a liquid feeding pipe that is arranged concentrically with the nozzle with a gap around the outer periphery of the nozzle and supplies the liquid from the outer periphery. It is preferable that the tip from which the liquid in the liquid feeding tube protrudes protrudes from the tip of the nozzle.
  • the cellulose polymer is preferably at least one of cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, nitrocellulose, ethylcellulose, and carboxymethylethylcellulose.
  • the method for producing a nonwoven fabric of the present invention includes a solution in which a cellulosic polymer is dissolved in a solvent and is charged to a first polarity from a nozzle.
  • a liquid having a lower concentration of the cellulosic polymer than the solution is supplied at a flow rate in a volume within the range of 5% or more and 20% or less, and the periphery of the solution from the tip is covered with the liquid.
  • the moving collector charged to the second polarity opposite to the polarity attracts the solution from the nozzle and collects it as a nanofiber on the support placed on the collector, and supports the collected nanofiber. It is configured as a non-woven fabric by being accumulated on the body.
  • a nanofiber manufacturing apparatus 150 shown in FIG. 1 is for manufacturing a nanofiber 46 from a solution 25 in which a cellulose polymer is dissolved in a solvent.
  • the nanofiber manufacturing apparatus 150 includes a spinning chamber 151, a solution supply unit 12, a nozzle 13, a coating solution supply unit 154 as a supply unit that supplies the coating solution 161, an accumulation unit 15, and a power source 65.
  • the spinning chamber 151 contains, for example, the nozzle 13, the liquid feeding pipe 160 of the coating liquid supply unit 154, a part of the accumulating unit 15, and the like, and is configured to be hermetically sealed to prevent solvent gas from leaking to the outside. is doing.
  • the solvent gas is obtained by vaporizing the solvent of the solution 25.
  • the solvent may be a simple substance or a mixture composed of a plurality of compounds.
  • a nozzle 13 is disposed in the upper part of the spinning chamber 151.
  • the nozzle 13 is for discharging the solution 25 in a state of being charged to the first polarity by the power source 65 as will be described later.
  • the nozzle 13 is formed of a cylinder, and the solution 25 is discharged from an opening 13a (hereinafter referred to as a tip opening) 13a.
  • the nozzle 13 is made of stainless steel having an outer diameter of 0.65 mm and an inner diameter of 0.4 mm, for example, and is cut so that a tip opening edge portion 13b around the tip opening 13a is orthogonal to the cylinder center direction.
  • the front end opening edge 13b which is the cut surface, is polished flat.
  • the liquid supply pipe 160 of the coating liquid supply unit 154 is disposed outside the nozzle 13 so as to be concentric with the nozzle 13.
  • the liquid feeding pipe 160 is a circular pipe disposed with a gap through which a coating liquid 161 described later flows between the outer periphery of the nozzle 13 and has an inner diameter larger than the outer diameter of the nozzle 13.
  • the concentricity does not necessarily have to be strict and may be substantially concentric with a deviation within 5% with respect to the inner diameter of the nozzle 13.
  • the liquid feeding pipe 160 forms a liquid feeding slit 162 between the tip opening 13 a of the nozzle 13 and discharges the coating liquid 161 from the liquid feeding slit 162.
  • the coating liquid 161 is supplied to the tip of the nozzle 13, and the periphery of the solution 25 coming out from the tip opening 13 a is covered with the coating liquid 161.
  • the coating liquid 161 is a liquid for covering the periphery of the solution 25 that has come out of the tip opening 13a.
  • the liquid feeding pipe 160 is made of stainless steel having an outer diameter of 11 mm and an inner diameter of 10 mm, for example, and the nozzle 13 is held by a spacer (not shown) so that the cylindrical center of the nozzle 13 and the cylindrical core of the liquid feeding pipe 160 coincide. ing.
  • the material of the nozzle 13 and the liquid feeding tube 160 may be made of a conductive material such as an aluminum alloy, a copper alloy, or a titanium alloy instead of stainless steel.
  • the solution 25 may come out of the tip opening 13a in a state where a voltage is applied in contact with the metal member at any location and is charged to the first polarity. Therefore, the tip opening 13a does not necessarily need to be made of a conductive material as long as a voltage is applied at any location and the first opening is charged when leaving the tip opening 13a.
  • the processing accuracy of the tip 13c of the nozzle 13 is important for the generation of the Taylor cone 44 and the stabilization of the spinning jet 45 extending from the Taylor cone. Therefore, for example, it is preferable that the tip 13c is coated with a fluorine-based material or the like because the nozzle 13 is kept clean.
  • the tip 160a of the liquid feeding tube 160 protrudes with a protruding amount L1 of, for example, about 5 mm with respect to the tip opening 13a.
  • a protruding amount L1 of, for example, about 5 mm with respect to the tip opening 13a.
  • the protruding amount L1 is preferably changed in accordance with the inner diameters of the nozzle 13 and the liquid feeding pipe 160, and is preferably set to a protruding amount L1 that more reliably prevents the surface of the formed Taylor cone 44 from drying.
  • the above-described coating liquid 161 is a liquid for covering the periphery of the solution 25 exiting from the tip opening 13a and the Taylor cone 44 formed from this solution, and includes the same substance as the solvent component of the solution 25. That is, the coating liquid 161 and the solvent of the solution 25 contain common components. For example, when the solvent of the solution 25 is a mixture, the coating liquid 161 may include at least one component thereof.
  • the coating liquid 161 may contain a cellulose-based polymer, and in this embodiment, the cellulose-based triacetate (TAC) is included as in the solution 25 as the cellulose-based polymer.
  • the concentration of TAC in the coating liquid 161 is 3% by mass, which is lower than the cellulose polymer concentration C in the solution 25 described later.
  • the coating liquid 161 may not contain a cellulosic polymer. That is, the concentration of the cellulose polymer in the coating liquid 161 may be 0 (zero), and the coating liquid 161 only needs to have a lower concentration of the cellulose polymer than in the solution 25.
  • the coating liquid 161 contains a cellulosic polymer
  • the cellulosic polymer is preferably the same substance as the cellulosic polymer contained in the solution 25.
  • a pipe 32 of the solution supply unit 12 is connected to the base end of the nozzle 13.
  • the solution supply unit 12 is for supplying the aforementioned solution 25 to the nozzle 13 of the spinning chamber 151.
  • the solution supply unit 12 includes a storage container 30, a pump 31, and a pipe 32.
  • the storage container 30 stores the solution 25 as a constant temperature within a range of 5 ° C. or higher and 40 ° C. or lower. Thereby, the temperature of the solution 25 which comes out of the nozzle 13 is made into the range of 5 to 40 degreeC. When the temperature of the solution 25 coming out of the nozzle 13 is 5 ° C.
  • the atmosphere (usually air) in the spinning area from the tip opening 13a to the support 60 on the collector 50 is compared to the case of less than 5 ° C. Condensation of the contained moisture is more reliably suppressed, and the nanofiber 46 is more stably manufactured from the solution 25 that has exited from the tip opening 13a.
  • the temperature is 40 ° C. or lower, the evaporation of the solvent is suppressed as compared with the case where the temperature is higher than 40 ° C., and the formation of liquid balls in the tip opening 13a is more reliably suppressed.
  • the pump 31 sends the solution 25 from the storage container 30 to the nozzle 13 via the pipe 32.
  • the flow rate of the solution 25 delivered from the nozzle 13 can be adjusted.
  • the flow rate of the solution 25 is 4 cm 3 / hour, but the flow rate is not limited to this.
  • the concentration C of the cellulose polymer in the solution 25 is preferably in the range of 2% by mass to 15% by mass. Thereby, manufacture of the nanofiber 46 and the nonwoven fabric 120 under the supply of the coating liquid 161 is stably continued.
  • the concentration C is more preferably in the range of 2% by mass or more and 10% by mass or less, and further preferably in the range of 2% by mass or more and 5% by mass or less.
  • concentration C is a value calculated
  • the concentration C is 4% by mass.
  • a pipe 38 of the coating liquid supply unit 154 is connected to the proximal end of the liquid feeding pipe 160.
  • the coating liquid supply unit 154 includes the above-described liquid feeding pipe 160, the flow rate adjustment valve 36, and the pipe 38.
  • the flow rate adjusting valve 36 is disposed outside the spinning chamber 11, but may be disposed inside the spinning chamber 11.
  • the flow rate adjusting valve 36 adjusts the flow rate of the coating liquid 161 from the liquid feeding slit 162.
  • the coating liquid 161 is discharged from the liquid feeding slit 162 at a flow rate ratio in the range of 5% to 20% with respect to the solution 25 from the tip opening 13a.
  • This flow rate is in volume. That is, when the flow rate in the volume of the solution 25 from the tip opening 13a is set to 100, it means that the flow rate in the volume of the coating liquid 161 from the liquid feeding slit 162 is in the range of 5 to 20.
  • the flow rate ratio is 5% or more, the coating liquid 161 reliably covers the periphery of the solution 25 coming out of the tip opening 13a as compared with the case of less than 5%.
  • the concentration of the cellulosic polymer does not decrease excessively in the solution 25 exiting from the tip opening 13a as compared with the case where the flow rate ratio is greater than 20%.
  • the flow rate ratio is more preferably in the range of 5% to 15%, and still more preferably in the range of 5% to 10%.
  • the accumulation unit 15 is disposed below the nozzle 13.
  • the stacking unit 15 includes a collector 50, a collector rotating unit 51, a support body supply unit 52, and a support body winding unit 53.
  • the collector 50 is for collecting the solution 25 exiting from the nozzle 13 as a nanofiber 46, and in this embodiment, collects it on a support 60 described later.
  • the collector 50 is composed of a band-shaped metal (for example, stainless steel) endless belt.
  • the collector 50 is not limited to stainless steel, and may be formed of a material that is charged by applying a voltage from the power source 65.
  • the collector rotating unit 51 is composed of a pair of rollers 55 and 56, a motor 57, and the like. The collector 50 is stretched horizontally around a pair of rollers 55 and 56.
  • a motor 57 disposed outside the spinning chamber 151 is connected to the shaft of one roller 55, and rotates the roller 55 at a predetermined speed. This rotation causes the collector 50 to circulate between the pair of rollers 55 and 56.
  • the moving speed of the collector 50 is 10 cm / hour, but is not limited to this.
  • the support body 60 made of a strip-shaped aluminum sheet (aluminum sheet) is supplied to the collector 50 by the support body supply section 52.
  • the support body 60 in the present embodiment has a thickness of approximately 25 ⁇ m.
  • the support 60 is for obtaining the nonwoven fabric 120 by accumulating (depositing) the nanofibers 46.
  • the support body 60 on the collector 50 is wound up by the support body winding part 53.
  • the support body supply unit 52 has a delivery shaft 52a.
  • a support roll 54 is attached to the delivery shaft 52a.
  • the support roll 54 is configured by winding the support 60.
  • the support winding portion 53 has a winding shaft 58.
  • the winding shaft 58 is rotated by a motor (not shown), and the support body 60 on which the nonwoven fabric 120 is formed is wound around the core 61 to be set.
  • the nonwoven fabric 120 is formed by integrating the nanofibers 46.
  • the nanofiber manufacturing apparatus 150 has a function of manufacturing the nonwoven fabric 120 in addition to the function of manufacturing the nanofiber 46.
  • the moving speed of the collector 50 and the moving speed of the support 60 are preferably the same so that friction does not occur between them. The same speed need not be exact. Further, the support 60 may be placed on the collector 50 and moved by the movement of the collector 50.
  • the nanofibers 46 may be directly accumulated on the collector 50 to form the nonwoven fabric 120.
  • the nonwoven fabric 120 may stick and be difficult to peel off. Therefore, as in this embodiment, it is preferable to guide the support body 60 on which the nonwoven fabric 120 is difficult to stick to the collector 50 and to accumulate the nanofibers 46 on the support body 60.
  • the power source 65 is a voltage application unit that applies a voltage to the nozzle 13 and the collector 50 to charge the nozzle to the first polarity, and charges the collector 50 to the second polarity opposite to the first polarity. .
  • the nozzle 13 is charged to minus ( ⁇ ) and the collector 50 is charged to plus (+).
  • the polarity of the nozzle 13 and the collector 50 may be reversed.
  • the voltage applied to the nozzle 13 and the collector 50 is 35 kV.
  • the distance L2 between the tip opening 13a of the nozzle 13 and the collector 50 varies depending on the type of the cellulose polymer and the solvent, the mass ratio of the solvent in the solution 25, etc., but is preferably in the range of 30 mm to 300 mm. In the embodiment, it is 180 mm.
  • the distance L2 is 30 mm or more, the spun jet 45 formed by jetting is more reliably split by repulsion due to its own charge before reaching the collector 50, compared to a case where the distance L2 is shorter than 30 mm. Therefore, the thin nanofiber 46 can be obtained more reliably.
  • the solvent evaporates more reliably by splitting in this way, it is more reliably prevented that the non-woven fabric has the solvent remaining.
  • the voltage to apply can be restrained low compared with the case where distance L2 is 300 mm or less and it is too long exceeding 300 mm, abnormal discharge is suppressed.
  • the thickness of the obtained nanofiber 46 varies depending on the magnitude of the voltage applied to the nozzle 13 and the collector 50. From the viewpoint of forming a thin fiber, it is preferable that the voltage is as low as possible. However, if it is lowered too much, it may not be in the form of a fiber but may become a ball and adhere to the collector 50 in some cases. Conversely, when the voltage is increased, the fiber becomes thicker, and when it is increased too much, the insulation of the device may be broken. Therefore, the voltage applied to the nozzle 13 and the collector 50 is preferably in the range of 2 kV to 40 kV, particularly preferably in the range of 20 kV to 35 kV.
  • cellulose triacetate As the cellulose-based polymer, cellulose triacetate (TAC) is used in the present embodiment, but is not limited thereto. TAC, cellulose diacetate (DAC), cellulose propionate, cellulose butyrate, cellulose acetate propionate , Nitrocellulose, ethylcellulose, or carboxymethylethylcellulose may be used.
  • TAC cellulose triacetate
  • DAC cellulose diacetate
  • DAC cellulose propionate
  • cellulose butyrate cellulose acetate propionate
  • Nitrocellulose ethylcellulose, or carboxymethylethylcellulose
  • Solvents for dissolving the cellulose polymer include methanol, ethanol, isopropanol, butanol, benzyl alcohol, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl formate, ethyl formate, hexane, cyclohexane, dichloromethane Chloroform, carbon tetrachloride, benzene, toluene, xylene, dimethylformamide, NMP, diethyl ether, dioxane, tetrahydrofuran, 1-methoxy-2-propanol and the like. These may be used alone or in combination depending on the type of cellulosic polymer. In the present embodiment, a mixture of dichloromethane and NMP is used as the solvent.
  • the solvent When the solvent is composed of a single component, that is, when it is composed of one component, the formation of a liquid ball becomes remarkable when the boiling point of the solvent is about 50 ° C. or less.
  • the solution since a substance having a low boiling point has a high evaporation rate, the solution tends to form a liquid ball when used as a solvent.
  • a voltage is applied from the power source 65 to the nozzle 13 and the collector 50 that circulates and moves.
  • the solution 25 is continuously supplied from the storage container 30 to the nozzle 13, and the support body 60 is continuously supplied onto the moving collector 50.
  • the collector 50 that is positively charged by the application of the voltage attracts the solution 25 that has been negatively charged from the tip opening 13a, and a spinning jet 45 is formed.
  • the negatively charged spinning jet 45 splits into a smaller diameter due to repulsion due to its own charge while heading toward the collector 50, and accumulates on the support 60 as nanofibers 46.
  • the integrated nanofiber 46 is sent to the support winding portion 53 together with the support 60 as the nonwoven fabric 120.
  • the nonwoven fabric 120 is wound around the core 61 in a state where it overlaps with the support body 60.
  • the support body 60 having the nonwoven fabric 120 is removed from the winding shaft 58 in a roll form, and then cut into a desired size, for example, into a sheet shape.
  • the nonwoven fabric 120 is peeled off from the support body 60 according to a use, and is used.
  • the coating liquid 161 comes out from the liquid feeding slit 162 and is continuously supplied around the solution 25 coming out from the tip opening 13a. Thereby, since the coating liquid 161 is covered around the solution 25 from the tip opening 13a, the surface of the solution 25 coming out from the tip opening 13a is difficult to dry. Since the coating liquid 161 from the liquid feeding slit 162 is within a range of 5% or more and 20% or less with respect to the solution 25 from the tip opening 13a, the coating liquid 161 is surrounded around the solution 25 that has come out of the tip opening 13a. Is surely covered. Thereby, the Taylor cone 44 is formed reliably, and the formed Taylor cone 44 is hard to dry and is stably maintained.
  • the solution 25 exiting from the tip opening 13a does not excessively reduce the concentration of the cellulosic polymer by the coating liquid 161. Therefore, the spinning jet 45 is formed without cutting the solution 25 extending from the Taylor cone 44, and the nanofiber 46 is manufactured. Further, since the Taylor cone 44 is stabilized for a long time as described above, the nonwoven fabric made of the nanofibers 46 is stably manufactured.
  • the coating liquid 161 contains the same substance as that used as the solvent component of the solution 25, there is almost no difference in the solubility of the cellulosic polymer between the inside and the outside of the solution 25 exiting from the tip opening 13a. . For this reason, restrictions on the formulation of the solution 25 and the manufacturing conditions of the nanofiber 46 are reduced, and the degree of freedom is increased.
  • the coating liquid 161 has a lower cellulosic polymer concentration than the solution 25. For this reason, drying of the surface of the solution 25 coming out from the tip opening 13a is suppressed to form the Taylor cone 44, and drying of the surface of the formed Taylor cone 44 is also suppressed.
  • the coating liquid 161 reliably covers the periphery of the solution 25 that has come out of the tip opening 13a. There is no excessive decrease in the concentration of the cellulosic polymer. For this reason, the Taylor cone 44 is stably maintained, and the nanofiber 46 and the nonwoven fabric 120 are stably manufactured.
  • the liquid feeding pipe 160 is arranged on the outer periphery of the nozzle 13 concentrically with the nozzle 13, the entire periphery of the solution 25 coming out from the tip opening 13 a is more reliably covered with the coating liquid 161. For this reason, the Taylor cone 44 is more reliably formed, and the formed Taylor cone 44 is stabilized for a long time. Therefore, the nonwoven fabric which consists of the nanofiber 46 is manufactured stably.
  • the liquid feeding pipe 160 is arranged so as to protrude from the tip opening 13a of the nozzle 13, the formed Taylor cone 44 is more reliably covered with the coating liquid 161 and stabilized for a long time. For this reason, the nonwoven fabric which consists of nanofiber 46 is manufactured stably.
  • the coating liquid 161 covers the solution 25 coming out of the tip opening 13a and the Taylor cone 44 formed from the solution 25, the evaporation of the solvent of the solution 25 can be kept low. Thereby, the surface of the Taylor cone 44 does not become hard, and generation
  • the nanofiber 46 can be used for the production of biofilters, sensors, fuel cell electrode materials, precision filters, electronic paper, and the like.
  • a heat pipe wick that is used at a relatively low temperature has a large amount of heat to be transferred, and may be used for an ecosystem that uses underground heat, for example.
  • it can be used as a beauty pack material with a good texture.
  • the collector 50 has a smooth surface, but the shape of the collector 50 is not limited.
  • a cylindrical rotating body may be used instead of the collector 50.
  • the cylindrical nonwoven fabric is formed from the nanofibers 46 on the surface of the rotating body, the cylindrical nonwoven fabric is extracted from the rotating body after manufacturing and cut into a desired size and shape to obtain a predetermined nonwoven fabric product. It can be.
  • a cylindrical rotating body is used, a non-woven fabric cannot be continuously produced, but a uniform non-woven fabric product is easy to make. For this reason, there is a possibility that application to cell culture scaffolds, medical uses, and the like becomes easy. Further, by increasing the number of rotations of the rotator, the degree of orientation of the nanofiber can be increased, and an anisotropic product can be obtained.
  • the tip 160a of the liquid feeding pipe 160 protrudes from the tip opening 13a of the nozzle 13 so that the Taylor cone 44 is covered with the liquid feeding pipe 160.
  • the nozzle and the liquid feeding pipe are used.
  • the positional relationship of the tip with 160 is not limited to this.
  • the tip 170 a of the liquid feeding tube 170 may be positioned in accordance with the tip 13 c of the nozzle 13.
  • the tip 13c of the nozzle 13 is not hidden in the tip 170b of the liquid feeding tube 170, so that the tip 13c can be easily cleaned.
  • the same constituent members are denoted by the same reference numerals, and redundant description is omitted.
  • a guide tube 175 is movably attached to the distal end portion 170b of the liquid feeding tube 170 of the second embodiment.
  • the coating liquid 161 from the liquid feeding slit 162 covers the Taylor cone 44 by the guide pipe 175 and the liquid feeding pipe 170 at the guide position (see FIG. 4) where the guide pipe 175 is lowered. Therefore, drying of the surface of the Taylor cone 44 is reliably suppressed.
  • the tip 13c of the nozzle 13 can be exposed by sliding the guide tube 175 upward from the guide position to the retracted position. For this reason, the tip opening 13a of the nozzle 13 can be reliably cleaned.
  • the guide tube 175 may be urged so as to protrude toward the tip by a spring (not shown) or the like, and may be positioned at a protruding position and a retracted position by a click mechanism (not shown).
  • the liquid feeding pipe 160 and the liquid feeding pipe 170 are circular pipes having a uniform inner diameter and outer diameter, but the inner diameter and the outer diameter are coating liquid 161 like the liquid feeding pipe 180 of the fourth embodiment shown in FIG. And the circular pipe which is changing in the flow direction of solution 25 may be sufficient.
  • the liquid feeding pipe 180 has a tapered tapered portion 180c having an inner diameter and an outer diameter that gradually decrease in the flow direction of the coating liquid 161 and the solution 25, and a tip portion 180b having a uniform inner diameter and outer diameter.
  • the distal end portion 180b of the liquid feeding pipe 180 protrudes from the distal end 13c of the nozzle 13.
  • the distal end section 180b may be flush with the distal end 13c as in the liquid feeding pipe 170 of the second embodiment. Good.
  • the flow path of the coating liquid 161 is divided into four in the circumferential direction of the nozzle 13.
  • the flow path of the coating liquid 161 may be divided into a plurality of parts in the circumferential direction of the nozzle 13.
  • the partition member 190 c that partitions the flow path also has a holding function for holding the nozzle 13.
  • the tip 190b of the liquid feeding tube 190 protrudes from the tip 13c of the nozzle 13.
  • the tip 190b may be flush with the tip 13c as in the liquid feeding tube 170 of the second embodiment. Good.
  • the liquid feeding pipe 195 of the sixth embodiment shown in FIG. 7 is a hexagonal pipe.
  • the liquid feeding pipe is not limited to a circular pipe and may be a polygonal pipe.
  • the tip 195b of the liquid feeding tube 195 has its tip 195a protruding from the tip 13c of the nozzle 13, but may be positioned flush with the tip 13c as in the liquid feeding tube 170 of the second embodiment.
  • nozzle 13 only one nozzle 13 is used, but a plurality of nozzles 13 may be used.
  • the plurality of nozzles 13 be provided apart from each other in a direction orthogonal to the moving direction of the support 60.
  • the nozzles 13 may be arranged in a matrix in the moving direction of the support 60 and in a direction orthogonal to the moving direction.
  • the nanofiber 46 was manufactured as the nonwoven fabric 120 by the nanofiber manufacturing apparatus 150.
  • the flow rate of the solution 25 was 4 cm 3 / hour, and the flow rate of the coating liquid 161 from the liquid feeding slit 162 was 0.5 cm 3 / hour, which was smaller than the flow rate of the solution 25.
  • the concentration C of TAC as the cellulose polymer in the solution 25 was 4 mass%, and the concentration of TAC as the cellulose polymer in the coating liquid 161 was 3 mass%.
  • the composition of the solution 25 and the composition of the coating liquid 161 are as described above. Further, the material and size of the liquid feeding pipe 160 used, the protruding amount L1, the material and moving speed of the collector 50 and the support 60, the value of the applied voltage, and the like are as described above.
  • the nanofibers 46 could be manufactured continuously, and a long nonwoven fabric 120 was obtained.
  • Example 1 The conditions were the same as in Example 1 except that the coating liquid 161 was not supplied from the liquid feeding pipe 160.
  • the Taylor cone 44 was formed at the start of production. However, the shape of the Taylor cone 44 collapsed and a liquid ball was formed in about 5 minutes from the start of the formation of the spinning jet. Was interrupted. Several seconds later, the side of the liquid ball was torn and the yarn spouted out, but the formation of the spinning jet 45 was immediately interrupted. Thereafter, the spinning jet 45 was not formed, and the nanofiber 46 could not be manufactured.
  • Example 2 The conditions were the same as in Example 1 except that the flow rate of the coating liquid 161 from the liquid feeding slit 162 was 2 cm 3 / hour.
  • the Taylor cone 44 was formed at the start of production, but the shape of the Taylor cone 44 was not stable, and the nanofiber 46 was produced only intermittently.
  • Comparative Example 3 The same conditions as in Example 1 were used except that the coating liquid 161 in Example 1 was replaced with a coating liquid having a TAC concentration of 8% by mass. In Comparative Example 3, a liquid ball was formed, and the formation of the spinning jet 45 was intermittent. Yarns spout from the lower part and side part of the liquid ball, and as production continues, the liquid ball grows downward in an irregular shape and falls on the support 60 on the collector 50 in about 10 minutes from the start of production. did.

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Nonwoven Fabrics (AREA)
  • Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
  • Artificial Filaments (AREA)

Abstract

The present invention pertains to a nanofiber production process which comprises: discharging, from the tip of a nozzle (13), a solution (25) obtained by dissolving a cellulosic polymer in a solvent; and applying a voltage between the solution (25) and a collector (50) to form a spinning-solution jet (45) toward the collector (50) and produce a nanofiber (46). In the process, a covering liquid (161) supplied through a liquid feed pipe (160) is discharged through a liquid feed slit, which is the space between the wall of the liquid feed pipe (160) and the nozzle (13), at a flow rate which is 5-20% of that of the solution (25), thereby covering therewith the periphery of the solution (25) discharged from the tip orifice. The covering liquid (161) comprises a component which is the same as in the solvent of the solution (25), and has a cellulosic-polymer concentration lower than that of the solution (25).

Description

ナノファイバ製造方法及び装置、不織布製造方法Nanofiber manufacturing method and apparatus, nonwoven fabric manufacturing method
　本発明は、ナノファイバ製造方法及び装置、不織布製造方法に関する。 The present invention relates to a nanofiber manufacturing method and apparatus, and a nonwoven fabric manufacturing method.
　例えば数ｎｍ以上１０００ｎｍ未満のナノオーダの径を有する繊維（ナノファイバ）は、バイオフィルタ、センサ、燃料電池電極材、精密フィルタ、電子ペーパ等の製品の素材として利用されており、工学や医療等の各分野においての用途開発が盛んに行われている。 For example, fibers (nanofibers) having a nano-order diameter of several nm or more and less than 1000 nm are used as materials for products such as biofilters, sensors, fuel cell electrode materials, precision filters, electronic paper, etc. Development of applications in various fields is actively conducted.
　ナノファイバを製造する方法の一つに、電界紡糸法（エレクトロスピニング法）がある。電界紡糸法は、ノズルとコレクタと電源とを有する電界紡糸装置(エレクトロスピニング装置）を用いて行われる（特許文献１参照）。電源によりノズルとコレクタとの間に電圧を印加し、例えば、ノズルをマイナス、コレクタをプラスに帯電させる。 One method for producing nanofibers is the electrospinning method (electrospinning method). The electrospinning method is performed using an electrospinning device (electrospinning device) having a nozzle, a collector, and a power source (see Patent Document 1). A voltage is applied between the nozzle and the collector by the power source, and for example, the nozzle is negatively charged and the collector is positively charged.
　電圧を印加した状態でノズルから原料である溶液を出すと、ノズルの先端の開口（以下、先端開口と称する）に溶液で構成される円錐状の突起が形成される。この円錐状の突起は、テイラーコーンと呼ばれる。印加電圧を徐々に増加し、クーロン力が溶液の表面張力を上回ると、テイラーコーンの先端から溶液が伸びて、紡糸ジェットが形成される。紡糸ジェットはクーロン力によってコレクタまで移動し、コレクタ上でナノファイバとして捕集される。 When a solution as a raw material is taken out from the nozzle in a state where a voltage is applied, a conical protrusion composed of the solution is formed at the opening at the tip of the nozzle (hereinafter referred to as the tip opening). This conical protrusion is called a Taylor cone. When the applied voltage is gradually increased and the Coulomb force exceeds the surface tension of the solution, the solution extends from the tip of the Taylor cone and a spinning jet is formed. The spinning jet moves to the collector by Coulomb force and is collected as nanofibers on the collector.
　ノズルから送られる溶液に蒸発しやすい溶媒（例えば揮発性の高い溶媒）を使用する場合には、先端開口で溶液が固化し、詰まることがある。また、ある程度固化した溶液が先端開口から離れると、コレクタ上に集積されたナノファイバの収集面に、固化した溶液が落ちてしまうことがある。このように溶液の詰まりや固化によって、製品の品質の低下や、製品としての使用が不可能になる。このため、特許文献２では、クリーニング手段を用いて、先端開口に柔軟部材を接触させて固化した溶液を除去したり、先端開口を吸引して固化した溶液を除去したりしている。 When using a solvent that easily evaporates (for example, a highly volatile solvent) for the solution sent from the nozzle, the solution may solidify and clog at the opening of the tip. Moreover, when the solution solidified to some extent moves away from the opening of the tip, the solidified solution may fall on the collecting surface of the nanofibers collected on the collector. Thus, the clogging or solidification of the solution makes it impossible to reduce the quality of the product or to use it as a product. For this reason, in Patent Document 2, the cleaning means is used to remove the solidified solution by bringing the flexible member into contact with the tip opening, or to remove the solidified solution by sucking the tip opening.
　特許文献３では、ノズルの先端開口から所定距離だけ離した位置にエア吹付部を設け、紡糸ジェットの進行方向にエア吹付部によりエアを吹き付けて、紡糸ジェットのコレクタへの移動を促進させ、ナノファイバの製造量を増加させている。 In Patent Document 3, an air spraying portion is provided at a position separated from the nozzle tip opening by a predetermined distance, and air is sprayed by the air spraying portion in the traveling direction of the spinning jet to promote the movement of the spinning jet to the collector. Increasing fiber production.
特開２００５－３３０６２４号公報JP 2005-330624 A 特開２００８－２０２１６９号公報JP 2008-202169 A 特開２０１４－４７４４０号公報JP 2014-47440 A
　特許文献２に示されるように、ノズルをクリーニングステーションに移動させて先端開口に柔軟部材を接触させて固化した溶液を除去する方法では、先端開口に柔軟部材を接触させることにより柔軟部材やノズルが撓む。そして、柔軟部材を先端開口から離れた際に撓んだ柔軟部材やノズルが元の姿勢に戻り、この戻る際の勢いで柔軟部材や先端開口に付着している固化した溶液を跳ね飛ばしてしまうことがあり、長時間の安定した製造が難しいことがある。 As shown in Patent Document 2, in the method of moving the nozzle to the cleaning station and bringing the flexible member into contact with the tip opening to remove the solidified solution, the flexible member or nozzle is moved by bringing the flexible member into contact with the tip opening. Bend. When the flexible member is moved away from the tip opening, the flexible member or nozzle that is bent returns to the original posture, and the solidified solution adhering to the flexible member or the tip opening is splashed off by the moment of return. In some cases, stable production for a long time may be difficult.
　また、吸引による先端開口のクリーニングでは、蒸発しやすい溶媒の場合には固化した溶液がかなり硬くなるため、強い吸引が必要になる。そのために紡糸装置内部の風の流れに乱れが生じて、コレクタ上に捕集されるナノファイバが均一でなくなり、製品の品質が著しく低下することがある。 Also, when the tip opening is cleaned by suction, the solidified solution becomes considerably hard in the case of a solvent that easily evaporates, and thus strong suction is required. As a result, the wind flow inside the spinning device is disturbed, and the nanofibers collected on the collector are not uniform, and the quality of the product may be significantly degraded.
　ところで、たとえばポリビニルアルコールの希薄水溶液のような原料を用いると、テイラーコーンが安定的に形成され、紡糸ジェット及びファイバの飛翔も安定する。しかし、溶媒の蒸発しやすい溶液（例えば溶媒の蒸発速度が速い溶液）では、テイラーコーンが形成できず、また形成されたとしても維持されず、ノズルから押し出された溶液の表面の溶媒がはやく蒸発することによって、液玉が発生することがある。液玉は、テイラーコーンのような略円錐状ではなく略球状になっており、表面は溶媒蒸発により粘度が上昇して皮が形成され、内部は溶媒濃度の高い溶液のままになっている。液玉が発生してしまうと、充分に電荷がかかっていても、表面からの溶液の吹き出しが困難になり、紡糸ジェットが噴出しても飛翔が不連続になって均一な太さのナノファイバの形成が困難になる。 By the way, when a raw material such as a dilute aqueous solution of polyvinyl alcohol is used, a Taylor cone is stably formed, and the spinning jet and the flying of the fiber are also stabilized. However, in a solution in which the solvent easily evaporates (for example, a solution having a high solvent evaporation rate), a Taylor cone cannot be formed, and even if it is formed, the solvent on the surface of the solution extruded from the nozzle evaporates quickly. By doing so, a liquid ball may be generated. The liquid ball has a substantially spherical shape instead of a substantially conical shape like a Taylor cone, and the surface is increased in viscosity by evaporation of the solvent to form a skin, and the inside remains as a solution having a high solvent concentration. When liquid balls are generated, it becomes difficult to blow out the solution from the surface even if there is sufficient charge, and even if the spinning jet is ejected, the flight is discontinuous and the nanofiber has a uniform thickness. It becomes difficult to form.
　また、液玉は装置の振動などによって落下することもあり、コレクタ上に不織布のような形態で集積されるナノファイバに貼り付いて欠陥となる。このため、集積したナノファイバが製品として使用できなくなったり、例えば不織布としての品質が低下したりすることがある。 Also, the liquid ball may drop due to the vibration of the apparatus, etc., and sticks to the nanofiber accumulated on the collector in the form of a non-woven fabric and becomes a defect. For this reason, the integrated nanofiber may become unusable as a product, or the quality as, for example, a nonwoven fabric may deteriorate.
　このように、特許文献２の電界紡糸方法では、ノズル先端での溶液の固化が原因で液玉が発生しているのに、対処療法的に液玉を洗浄して取り除くだけであり、根本的な解決には至っていない。 As described above, in the electrospinning method of Patent Document 2, although the liquid balls are generated due to the solidification of the solution at the nozzle tip, the liquid balls are only washed and removed in a coping therapy. No solution has been reached.
　特許文献３の電界紡糸装置では、紡糸ジェットの進行方向にエア吹付部によりエアを吹き付けて、紡糸ジェットのコレクタへの移動を促進させ、ナノファイバの製造量を増加させている。しかし、目的は紡糸ジェットのコレクタへの移動促進であり、液玉の抑制については考慮されていない。 In the electrospinning apparatus of Patent Document 3, air is blown by an air blowing portion in the traveling direction of the spinning jet to promote the movement of the spinning jet to the collector, and the production amount of nanofibers is increased. However, the purpose is to promote the movement of the spinning jet to the collector and no consideration is given to the suppression of the liquid balls.
　このように、従来の電界紡糸装置においては、テイラーコーンの形成及びその維持に関して十分な検討がなされていないのが現状である。本発明は、上記問題点に鑑み、テイラーコーンを安定的に維持し、ナノファイバを安定して製造することができるナノファイバ製造方法及び装置、不織布製造方法を提供することを目的とする。 As described above, in the conventional electrospinning apparatus, it is the present situation that sufficient studies have not been made on the formation and maintenance of the Taylor cone. An object of this invention is to provide the nanofiber manufacturing method and apparatus which can maintain a Taylor cone stably, and can manufacture a nanofiber stably, and a nonwoven fabric manufacturing method in view of the said problem.
　本発明のナノファイバ製造方法は、セルロース系ポリマーが溶媒に溶解し、第１の極性に帯電された状態の溶液をノズルから出し、ノズルの溶液が出る先端に、溶媒の成分と同じ物質を含み溶液よりもセルロース系ポリマーの濃度が低い液を溶液に対して５％以上２０％以下の範囲内の体積での流量割合で供給して、先端から出た溶液の周囲を液で覆い、第１の極性と逆極性の第２の極性に帯電されたコレクタにより、ノズルから出た溶液を誘引しナノファイバとして捕集することを特徴として構成されている。 In the nanofiber manufacturing method of the present invention, a cellulosic polymer is dissolved in a solvent, a solution charged in a first polarity is taken out from the nozzle, and the same substance as the solvent component is included at the tip from which the solution of the nozzle comes out. A liquid having a lower concentration of the cellulosic polymer than the solution is supplied at a flow rate in a volume within the range of 5% to 20% of the solution, and the periphery of the solution from the tip is covered with the liquid. It is characterized by attracting the solution from the nozzle and collecting it as nanofibers by means of a collector charged to a second polarity opposite to the polarity.
　ノズルとノズルの外周に隙間をもってノズルと同心で配された送液管との間から液を出すことにより、液を供給することが好ましい。送液管の液が出る先端は、ノズルの先端よりも突出していることが好ましい。 It is preferable to supply the liquid by discharging the liquid from between the nozzle and a liquid feeding pipe arranged concentrically with the nozzle with a gap around the nozzle. It is preferable that the tip from which the liquid in the liquid feeding tube protrudes protrudes from the tip of the nozzle.
　セルロース系ポリマーは、セルローストリアセテート、セルロースジアセテート、セルロースプロピオネート、セルロースブチレート、セルロースアセテートプロピオネート、ニトロセルロース、エチルセルロース、カルボキシメチルエチルセルロースの少なくともいずれかひとつであることが好ましい。 The cellulose polymer is preferably at least one of cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, nitrocellulose, ethylcellulose, and carboxymethylethylcellulose.
　本発明のナノファイバ製造装置は、セルロース系ポリマーが溶媒に溶解した溶液を出すノズルと、ノズルの溶液が出る先端に、溶媒の成分と同じ物質を含み溶液よりもセルロース系ポリマーの濃度が低い液を溶液に対して５％以上２０％以下の範囲内の体積での流量割合で供給して、先端から出た溶液の周囲を液で覆う供給部と、ノズルから出た溶液を誘引し、ナノファイバとして捕集するコレクタと、ノズルから出る溶液とコレクタとに電圧を印加することにより溶液とコレクタとを逆極性に帯電させる電圧印加部とを備えることを特徴として構成されている。 The nanofiber production apparatus of the present invention includes a nozzle for dispensing a solution in which a cellulosic polymer is dissolved in a solvent, and a liquid containing a substance that is the same as the solvent component at the tip of the nozzle solution and having a lower concentration of the cellulosic polymer than the solution. Is supplied at a flow rate ratio in a volume within the range of 5% or more and 20% or less with respect to the solution, and the supply part that covers the periphery of the solution that has come out from the tip with the liquid and the solution that comes out from the nozzle are attracted, The apparatus includes a collector that collects as a fiber, and a voltage application unit that charges the solution and the collector with opposite polarities by applying a voltage to the solution and the collector that come out of the nozzle.
　ノズルの外周に隙間をもってノズルと同心で配され、外周との間から液を出して供給する送液管を備えることが好ましい。送液管の液が出る先端は、ノズルの先端よりも突出していることが好ましい。 It is preferable to provide a liquid feeding pipe that is arranged concentrically with the nozzle with a gap around the outer periphery of the nozzle and supplies the liquid from the outer periphery. It is preferable that the tip from which the liquid in the liquid feeding tube protrudes protrudes from the tip of the nozzle.
　セルロース系ポリマーは、セルローストリアセテート、セルロースジアセテート、セルロースプロピオネート、セルロースブチレート、セルロースアセテートプロピオネート、ニトロセルロース、エチルセルロース、カルボキシメチルエチルセルロースの少なくともいずれかひとつであることが好ましい。 The cellulose polymer is preferably at least one of cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, nitrocellulose, ethylcellulose, and carboxymethylethylcellulose.
　本発明の不織布製造方法は、セルロース系ポリマーが溶媒に溶解し、第１の極性に帯電された状態の溶液をノズルから出し、ノズルの溶液が出る先端に、溶媒の成分と同じ物質を含み溶液よりもセルロース系ポリマーの濃度が低い液を溶液に対して５％以上２０％以下の範囲内の体積での流量割合で供給して、先端から出た溶液の周囲を液で覆い、第１の極性と逆極性の第２の極性に帯電された移動するコレクタにより、ノズルから出た溶液を誘引してコレクタ上に配された支持体にナノファイバとして捕集し、捕集したナノファイバを支持体上で集積させることにより不織布とすることを特徴として構成されている。 The method for producing a nonwoven fabric of the present invention includes a solution in which a cellulosic polymer is dissolved in a solvent and is charged to a first polarity from a nozzle. A liquid having a lower concentration of the cellulosic polymer than the solution is supplied at a flow rate in a volume within the range of 5% or more and 20% or less, and the periphery of the solution from the tip is covered with the liquid. The moving collector charged to the second polarity opposite to the polarity attracts the solution from the nozzle and collects it as a nanofiber on the support placed on the collector, and supports the collected nanofiber. It is configured as a non-woven fabric by being accumulated on the body.
　本発明によれば、テイラーコーンを安定的に維持し、セルロース系ポリマーが溶媒に溶解した溶液からナノファイバを安定して製造することができる。 According to the present invention, it is possible to stably produce a nanofiber from a solution in which a Taylor corn is stably maintained and a cellulose polymer is dissolved in a solvent.
本発明の一実施形態を実施したナノファイバ製造装置の概略図である。It is the schematic of the nanofiber manufacturing apparatus which implemented one Embodiment of this invention. ノズル及び送風管の先端部を示す断面概略図である。It is a cross-sectional schematic diagram which shows the front-end | tip part of a nozzle and a blast pipe. 第２実施形態であるノズル及び送風管の断面概略図である。It is a section schematic diagram of a nozzle and an air duct which are the 2nd embodiment. 第３実施形態であるノズル及び送風管の断面概略図である。It is a section schematic diagram of a nozzle and a blower pipe which is a 3rd embodiment. 第４実施形態であるノズル及び送風管の概略を示す斜視図である。It is a perspective view which shows the outline of the nozzle and blower pipe which are 4th Embodiment. 第５実施形態であるノズル及び送風管の概略を示す斜視図である。It is a perspective view which shows the outline of the nozzle which is 5th Embodiment, and an air duct. 第６実施形態であるノズル及び送風管の概略を示す斜視図である。It is a perspective view which shows the outline of the nozzle which is 6th Embodiment, and an air duct.
　図１に示すナノファイバ製造装置１５０は、セルロース系ポリマーが溶媒に溶解した溶液２５からナノファイバ４６を製造するためのものである。ナノファイバ製造装置１５０は、紡糸室１５１と、溶液供給部１２と、ノズル１３と、被覆液１６１を供給する供給部としての被覆液供給部１５４と、集積部１５と、電源６５とを備える。紡糸室１５１は、例えば、ノズル１３、被覆液供給部１５４の送液管１６０、集積部１５の一部などを収容して、密閉可能に構成されており、溶媒ガスが外部に洩れることを防止している。溶媒ガスは、溶液２５の溶媒が気化したものである。溶媒は、単体でもよいし、複数の化合物からなる混合物であってもよい。本実施形態においては、ジクロロメタンとＮ－メチルピロリドン（ＮＭＰ）との混合物を用いており、質量比はジクロロメタン：ＮＭＰ＝８：２である。溶媒についての詳細は後述する。 A nanofiber manufacturing apparatus 150 shown in FIG. 1 is for manufacturing a nanofiber 46 from a solution 25 in which a cellulose polymer is dissolved in a solvent. The nanofiber manufacturing apparatus 150 includes a spinning chamber 151, a solution supply unit 12, a nozzle 13, a coating solution supply unit 154 as a supply unit that supplies the coating solution 161, an accumulation unit 15, and a power source 65. The spinning chamber 151 contains, for example, the nozzle 13, the liquid feeding pipe 160 of the coating liquid supply unit 154, a part of the accumulating unit 15, and the like, and is configured to be hermetically sealed to prevent solvent gas from leaking to the outside. is doing. The solvent gas is obtained by vaporizing the solvent of the solution 25. The solvent may be a simple substance or a mixture composed of a plurality of compounds. In this embodiment, a mixture of dichloromethane and N-methylpyrrolidone (NMP) is used, and the mass ratio is dichloromethane: NMP = 8: 2. Details of the solvent will be described later.
　紡糸室１５１内の上部には、ノズル１３が配される。ノズル１３は、後述のように電源６５により溶液２５を第１の極性に帯電された状態で出すためのものである。図２に示すように、ノズル１３は円筒から構成されており、先端の開口（以下、先端開口と称する）１３ａから溶液２５を出す。ノズル１３は、例えば外径が０．６５ｍｍで内径が０．４ｍｍのステンレス製であり、先端開口１３ａの周りの先端開口縁部１３ｂが筒心方向に直交するように切断されている。この切断面である先端開口縁部１３ｂは、平坦に研磨されている。 A nozzle 13 is disposed in the upper part of the spinning chamber 151. The nozzle 13 is for discharging the solution 25 in a state of being charged to the first polarity by the power source 65 as will be described later. As shown in FIG. 2, the nozzle 13 is formed of a cylinder, and the solution 25 is discharged from an opening 13a (hereinafter referred to as a tip opening) 13a. The nozzle 13 is made of stainless steel having an outer diameter of 0.65 mm and an inner diameter of 0.4 mm, for example, and is cut so that a tip opening edge portion 13b around the tip opening 13a is orthogonal to the cylinder center direction. The front end opening edge 13b, which is the cut surface, is polished flat.
　ノズル１３の外側にはノズル１３と同心で、被覆液供給部１５４の送液管１６０が配される。送液管１６０は、ノズル１３の外周との間に後述の被覆液１６１が流れる隙間をもって配された円管であり、内径がノズル１３の外径よりも大きく形成されている。同心とは、必ずしも厳格でなくてもよく、ノズル１３の内径に対して５％以内でのずれがある略同心であってもよい。送液管１６０は、ノズル１３の先端開口１３ａとの間に送液スリット１６２を形成しており、この送液スリット１６２から被覆液１６１を出す。このように、ノズル１３の先端には被覆液１６１が供給されて、先端開口１３ａから出た溶液２５の周囲を被覆液１６１で覆う。このように、被覆液１６１は、先端開口１３ａから出た溶液２５の周囲を覆うための液である。 The liquid supply pipe 160 of the coating liquid supply unit 154 is disposed outside the nozzle 13 so as to be concentric with the nozzle 13. The liquid feeding pipe 160 is a circular pipe disposed with a gap through which a coating liquid 161 described later flows between the outer periphery of the nozzle 13 and has an inner diameter larger than the outer diameter of the nozzle 13. The concentricity does not necessarily have to be strict and may be substantially concentric with a deviation within 5% with respect to the inner diameter of the nozzle 13. The liquid feeding pipe 160 forms a liquid feeding slit 162 between the tip opening 13 a of the nozzle 13 and discharges the coating liquid 161 from the liquid feeding slit 162. In this way, the coating liquid 161 is supplied to the tip of the nozzle 13, and the periphery of the solution 25 coming out from the tip opening 13 a is covered with the coating liquid 161. Thus, the coating liquid 161 is a liquid for covering the periphery of the solution 25 that has come out of the tip opening 13a.
　送液管１６０は例えば外径が１１ｍｍで内径が１０ｍｍのステンレス製であり、ノズル１３の筒心と送液管１６０の筒心とが一致するように、図示省略のスペーサによりノズル１３を保持している。 The liquid feeding pipe 160 is made of stainless steel having an outer diameter of 11 mm and an inner diameter of 10 mm, for example, and the nozzle 13 is held by a spacer (not shown) so that the cylindrical center of the nozzle 13 and the cylindrical core of the liquid feeding pipe 160 coincide. ing.
　ノズル１３及び送液管１６０の素材はステンレスに代えて、例えばアルミニウム合金、銅合金、チタン合金等の導電性材料で構成してもよい。なお、電界紡糸のためには、溶液２５はいずれかの場所で金属部材に接して電圧が印加され、第１の極性に帯電した状態で先端開口１３ａから出ればよい。したがって、いずれかの場所で電圧が印加され、先端開口１３ａから出る際に第１の極性に帯電していれば、先端開口１３ａは必ずしも導電性材料である必要はない。なお、テイラーコーン４４の生成や、テイラーコーンから伸びる紡糸ジェット４５の安定化には、ノズル１３の先端１３ｃの加工精度が重要である。そこで、たとえばフッ素系材料などで先端１３ｃがコーティングされていると、ノズル１３が清浄な状態に保たれるので好ましい。 The material of the nozzle 13 and the liquid feeding tube 160 may be made of a conductive material such as an aluminum alloy, a copper alloy, or a titanium alloy instead of stainless steel. For electrospinning, the solution 25 may come out of the tip opening 13a in a state where a voltage is applied in contact with the metal member at any location and is charged to the first polarity. Therefore, the tip opening 13a does not necessarily need to be made of a conductive material as long as a voltage is applied at any location and the first opening is charged when leaving the tip opening 13a. The processing accuracy of the tip 13c of the nozzle 13 is important for the generation of the Taylor cone 44 and the stabilization of the spinning jet 45 extending from the Taylor cone. Therefore, for example, it is preferable that the tip 13c is coated with a fluorine-based material or the like because the nozzle 13 is kept clean.
　送液管１６０の先端１６０ａは、先端開口１３ａに対して例えば５ｍｍ程度の突出量Ｌ１で突出している。この突出した送液管１６０の先端部１６０ｂによって、ノズル１３から出た溶液２５で形成されるテイラーコーン４４がより確実に覆われる。突出量Ｌ１はノズル１３と送液管１６０との内径に対応して変えることが好ましく、形成されたテイラーコーン４４の表面の乾きをより確実に防止するような突出量Ｌ１とすることが好ましい。 The tip 160a of the liquid feeding tube 160 protrudes with a protruding amount L1 of, for example, about 5 mm with respect to the tip opening 13a. By the protruding end portion 160b of the liquid feeding pipe 160, the Taylor cone 44 formed by the solution 25 that has come out of the nozzle 13 is more reliably covered. The protruding amount L1 is preferably changed in accordance with the inner diameters of the nozzle 13 and the liquid feeding pipe 160, and is preferably set to a protruding amount L1 that more reliably prevents the surface of the formed Taylor cone 44 from drying.
　前述の被覆液１６１は、先端開口１３ａから出た溶液２５、及びこの溶液から形成されたテイラーコーン４４の周囲を覆うための液であり、溶液２５の溶媒の成分と同じ物質を含む。すなわち、被覆液１６１と、溶液２５の溶媒とは、共通した成分を含む。例えば溶液２５の溶媒が混合物である場合には、その少なくともひとつの成分を被覆液１６１は含めばよい。本実施形態の被覆液１６１は、溶液２５の溶媒を成すすべての成分を含んでおり、ジクロロメタンとＮＭＰとの混合物としている。またこれらの質量比はジクロロメタン：ＮＭＰ＝８：２である。 The above-described coating liquid 161 is a liquid for covering the periphery of the solution 25 exiting from the tip opening 13a and the Taylor cone 44 formed from this solution, and includes the same substance as the solvent component of the solution 25. That is, the coating liquid 161 and the solvent of the solution 25 contain common components. For example, when the solvent of the solution 25 is a mixture, the coating liquid 161 may include at least one component thereof. The coating liquid 161 of this embodiment contains all the components that constitute the solvent of the solution 25, and is a mixture of dichloromethane and NMP. Moreover, these mass ratios are dichloromethane: NMP = 8: 2.
　被覆液１６１は、セルロース系ポリマーを含んでいてもよく、本実施形態においては、セルロース系ポリマーとして溶液２５におけるものと同じくセルローストリアセテート（ＴＡＣ）を含んでいる。また被覆液１６１におけるＴＡＣの濃度は、後述の溶液２５におけるセルロース系ポリマー濃度Ｃよりも低い３質量％としている。被覆液１６１は、セルロース系ポリマーを含んでいなくてもよい。つまり、被覆液１６１におけるセルロース系ポリマーの濃度は０（ゼロ）であってもよく、被覆液１６１は、溶液２５におけるよりもセルロース系ポリマーの濃度が低ければよい。被覆液１６１がセルロース系ポリマーを含む場合のそのセルロース系ポリマーは、溶液２５に含まれているセルロース系ポリマーと同じ物質であることが好ましい。 The coating liquid 161 may contain a cellulose-based polymer, and in this embodiment, the cellulose-based triacetate (TAC) is included as in the solution 25 as the cellulose-based polymer. The concentration of TAC in the coating liquid 161 is 3% by mass, which is lower than the cellulose polymer concentration C in the solution 25 described later. The coating liquid 161 may not contain a cellulosic polymer. That is, the concentration of the cellulose polymer in the coating liquid 161 may be 0 (zero), and the coating liquid 161 only needs to have a lower concentration of the cellulose polymer than in the solution 25. When the coating liquid 161 contains a cellulosic polymer, the cellulosic polymer is preferably the same substance as the cellulosic polymer contained in the solution 25.
　図１に示すように、ノズル１３の基端には、溶液供給部１２の配管３２が接続されている。溶液供給部１２は、紡糸室１５１のノズル１３に前述の溶液２５を供給するためのものである。溶液供給部１２は、貯留容器３０とポンプ３１と配管３２とを備える。貯留容器３０は溶液２５を５℃以上４０℃以下の範囲内の一定温度として貯留する。これにより、ノズル１３から出る溶液２５の温度を、５℃以上４０℃以下の範囲内にしている。ノズル１３から出る溶液２５の温度が５℃以上である場合には、５℃未満の場合に比べて、先端開口１３ａとコレクタ５０上の支持体６０までの紡糸エリアの雰囲気（通常は空気）に含まれる水分の凝縮がより確実に抑えられ、先端開口１３ａから出た溶液２５からナノファイバ４６がより安定して製造される。４０℃以下である場合には、４０℃よりも高い場合に比べて溶媒の蒸発が抑えられ、先端開口１３ａにおける液玉の形成がより確実に抑制される。 As shown in FIG. 1, a pipe 32 of the solution supply unit 12 is connected to the base end of the nozzle 13. The solution supply unit 12 is for supplying the aforementioned solution 25 to the nozzle 13 of the spinning chamber 151. The solution supply unit 12 includes a storage container 30, a pump 31, and a pipe 32. The storage container 30 stores the solution 25 as a constant temperature within a range of 5 ° C. or higher and 40 ° C. or lower. Thereby, the temperature of the solution 25 which comes out of the nozzle 13 is made into the range of 5 to 40 degreeC. When the temperature of the solution 25 coming out of the nozzle 13 is 5 ° C. or higher, the atmosphere (usually air) in the spinning area from the tip opening 13a to the support 60 on the collector 50 is compared to the case of less than 5 ° C. Condensation of the contained moisture is more reliably suppressed, and the nanofiber 46 is more stably manufactured from the solution 25 that has exited from the tip opening 13a. When the temperature is 40 ° C. or lower, the evaporation of the solvent is suppressed as compared with the case where the temperature is higher than 40 ° C., and the formation of liquid balls in the tip opening 13a is more reliably suppressed.
　ポンプ３１は、配管３２を介して溶液２５を貯留容器３０からノズル１３に送る。ポンプ３１の回転数を変えることにより、ノズル１３から送り出す溶液２５の流量を調節することができる。本実施形態においては、溶液２５の流量を４ｃｍ３／時としているが、流量はこれに限定されない。ポンプ３１によってノズル１３に溶液２５が送られることにより、溶液２５は先端開口１３ａから出て、図２に示すように先端開口１３ａに略円錐状のテイラーコーン４４を形成する。 The pump 31 sends the solution 25 from the storage container 30 to the nozzle 13 via the pipe 32. By changing the number of rotations of the pump 31, the flow rate of the solution 25 delivered from the nozzle 13 can be adjusted. In the present embodiment, the flow rate of the solution 25 is 4 cm 3 / hour, but the flow rate is not limited to this. When the solution 25 is sent to the nozzle 13 by the pump 31, the solution 25 exits from the tip opening 13a and forms a substantially conical Taylor cone 44 in the tip opening 13a as shown in FIG.
　溶液２５におけるセルロース系ポリマーの濃度Ｃは、２質量％以上１５質量％以下の範囲内であることが好ましい。これにより、被覆液１６１の供給のもとでのナノファイバ４６及び不織布１２０の製造が安定して継続される。濃度Ｃは、２質量％以上１０質量％以下の範囲内であることがより好ましく、２質量％以上５質量％以下の範囲内であることがさらに好ましい。なお、上記の濃度Ｃは、溶媒の質量をＹ（単位；ｇ）、セルロース系ポリマーの質量をＰ（単位；ｇ）とするときに、｛Ｐ／（Ｐ＋Ｙ）｝×１００で求める値である。本実施形態では、濃度Ｃは４質量％としている。 The concentration C of the cellulose polymer in the solution 25 is preferably in the range of 2% by mass to 15% by mass. Thereby, manufacture of the nanofiber 46 and the nonwoven fabric 120 under the supply of the coating liquid 161 is stably continued. The concentration C is more preferably in the range of 2% by mass or more and 10% by mass or less, and further preferably in the range of 2% by mass or more and 5% by mass or less. In addition, said density | concentration C is a value calculated | required by {P / (P + Y)} * 100 when the mass of a solvent is set to Y (unit; g) and the mass of a cellulose-type polymer is set to P (unit; g). . In this embodiment, the concentration C is 4% by mass.
　図１に示すように、送液管１６０の基端には、被覆液供給部１５４の配管３８が接続されている。被覆液供給部１５４は、前述の送液管１６０と、流量調節バルブ３６と、配管３８とを備える。この例では、流量調節バルブ３６は、紡糸室１１外に配置しているが、紡糸室１１内に配置してもよい。 As shown in FIG. 1, a pipe 38 of the coating liquid supply unit 154 is connected to the proximal end of the liquid feeding pipe 160. The coating liquid supply unit 154 includes the above-described liquid feeding pipe 160, the flow rate adjustment valve 36, and the pipe 38. In this example, the flow rate adjusting valve 36 is disposed outside the spinning chamber 11, but may be disposed inside the spinning chamber 11.
　流量調節バルブ３６は、送液スリット１６２からの被覆液１６１の流量を調節する。この流量の調節によって、先端開口１３ａからの溶液２５に対して５％以上２０％以下の範囲内の流量割合で、被覆液１６１を送液スリット１６２から出す。この流量割合は、体積でのものである。すなわち、先端開口１３ａからの溶液２５の体積での流量を１００とするときに、送液スリット１６２からの被覆液１６１の体積での流量が５以上２０以下の範囲内であることを意味する。流量割合が５％以上であることにより、５％未満の場合と比べて、先端開口１３ａから出た溶液２５の周囲を被覆液１６１が確実に覆う。流量割合が２０％以下であることにより、２０％より大きい場合と比べて、先端開口１３ａから出た溶液２５は、セルロース系ポリマーの濃度が過度に低下することもない。この流量割合は、５％以上１５％以下の範囲内であることがより好ましく、５％以上１０％以下の範囲内であることがさらに好ましい。 The flow rate adjusting valve 36 adjusts the flow rate of the coating liquid 161 from the liquid feeding slit 162. By adjusting the flow rate, the coating liquid 161 is discharged from the liquid feeding slit 162 at a flow rate ratio in the range of 5% to 20% with respect to the solution 25 from the tip opening 13a. This flow rate is in volume. That is, when the flow rate in the volume of the solution 25 from the tip opening 13a is set to 100, it means that the flow rate in the volume of the coating liquid 161 from the liquid feeding slit 162 is in the range of 5 to 20. When the flow rate ratio is 5% or more, the coating liquid 161 reliably covers the periphery of the solution 25 coming out of the tip opening 13a as compared with the case of less than 5%. When the flow rate ratio is 20% or less, the concentration of the cellulosic polymer does not decrease excessively in the solution 25 exiting from the tip opening 13a as compared with the case where the flow rate ratio is greater than 20%. The flow rate ratio is more preferably in the range of 5% to 15%, and still more preferably in the range of 5% to 10%.
　ノズル１３の下方には集積部１５が配される。集積部１５は、コレクタ５０、コレクタ回転部５１、支持体供給部５２、及び支持体巻取り部５３を有する。コレクタ５０はノズル１３から出た溶液２５をナノファイバ４６として捕集するためのものであり、本実施形態では、後述の支持体６０上に捕集する。コレクタ５０は、帯状の金属製（例えばステンレス製）の無端ベルトから構成されている。コレクタ５０はステンレス製に限定されず、電源６５による電圧の印加により帯電する素材から形成されていればよい。コレクタ回転部５１は、１対のローラ５５，５６、モータ５７などから構成されている。コレクタ５０は、１対のローラ５５，５６に水平に掛け渡されている。一方のローラ５５の軸には紡糸室１５１の外に配されたモータ５７が接続されており、ローラ５５を所定速度で回転させる。この回転によりコレクタ５０は１対のローラ５５，５６間で循環するように移動する。本実施形態においては、コレクタ５０の移動速度は、１０ｃｍ／時としているが、これに限定されない。 The accumulation unit 15 is disposed below the nozzle 13. The stacking unit 15 includes a collector 50, a collector rotating unit 51, a support body supply unit 52, and a support body winding unit 53. The collector 50 is for collecting the solution 25 exiting from the nozzle 13 as a nanofiber 46, and in this embodiment, collects it on a support 60 described later. The collector 50 is composed of a band-shaped metal (for example, stainless steel) endless belt. The collector 50 is not limited to stainless steel, and may be formed of a material that is charged by applying a voltage from the power source 65. The collector rotating unit 51 is composed of a pair of rollers 55 and 56, a motor 57, and the like. The collector 50 is stretched horizontally around a pair of rollers 55 and 56. A motor 57 disposed outside the spinning chamber 151 is connected to the shaft of one roller 55, and rotates the roller 55 at a predetermined speed. This rotation causes the collector 50 to circulate between the pair of rollers 55 and 56. In this embodiment, the moving speed of the collector 50 is 10 cm / hour, but is not limited to this.
　コレクタ５０には支持体供給部５２によって帯状のアルミニウムシート（アルミシート）からなる支持体６０が供給される。本実施形態における支持体６０は、厚みが概ね２５μｍである。支持体６０は、ナノファイバ４６を集積（堆積）させて不織布１２０として得るためのものである。コレクタ５０上の支持体６０は、支持体巻取り部５３によって巻き取られる。支持体供給部５２は送出軸５２ａを有する。送出軸５２ａには支持体ロール５４が装着される。支持体ロール５４は支持体６０が巻き取られて構成されている。支持体巻取り部５３は巻取り軸５８を有する。巻取り軸５８は図示省略のモータにより回転され、セットされる巻芯６１に、不織布１２０が形成された支持体６０を巻き取る。不織布１２０は、ナノファイバ４６が集積されて形成されたものである。このように、このナノファイバ製造装置１５０は、ナノファイバ４６を製造する機能に加え、不織布１２０を製造する機能をもつ。コレクタ５０の移動速度と支持体６０の移動速度は両者の間に摩擦が生じることがないように同じにすることが好ましい。同じ速度とは厳密である必要はない。また、支持体６０は、コレクタ５０上に載せて、コレクタ５０の移動によって移動する態様にしてもよい。 The support body 60 made of a strip-shaped aluminum sheet (aluminum sheet) is supplied to the collector 50 by the support body supply section 52. The support body 60 in the present embodiment has a thickness of approximately 25 μm. The support 60 is for obtaining the nonwoven fabric 120 by accumulating (depositing) the nanofibers 46. The support body 60 on the collector 50 is wound up by the support body winding part 53. The support body supply unit 52 has a delivery shaft 52a. A support roll 54 is attached to the delivery shaft 52a. The support roll 54 is configured by winding the support 60. The support winding portion 53 has a winding shaft 58. The winding shaft 58 is rotated by a motor (not shown), and the support body 60 on which the nonwoven fabric 120 is formed is wound around the core 61 to be set. The nonwoven fabric 120 is formed by integrating the nanofibers 46. As described above, the nanofiber manufacturing apparatus 150 has a function of manufacturing the nonwoven fabric 120 in addition to the function of manufacturing the nanofiber 46. The moving speed of the collector 50 and the moving speed of the support 60 are preferably the same so that friction does not occur between them. The same speed need not be exact. Further, the support 60 may be placed on the collector 50 and moved by the movement of the collector 50.
　なお、コレクタ５０の上にナノファイバ４６を直接集積して不織布１２０を形成してもよいが、コレクタ５０を形成する素材や表面状態等によっては不織布１２０が貼り付いて剥がしにくいことがある。そのため、本実施形態のように、不織布１２０が貼り付きにくくされた支持体６０をコレクタ５０上に案内して、この支持体６０上にナノファイバ４６を集積することが好ましい。 Note that the nanofibers 46 may be directly accumulated on the collector 50 to form the nonwoven fabric 120. However, depending on the material forming the collector 50, the surface condition, and the like, the nonwoven fabric 120 may stick and be difficult to peel off. Therefore, as in this embodiment, it is preferable to guide the support body 60 on which the nonwoven fabric 120 is difficult to stick to the collector 50 and to accumulate the nanofibers 46 on the support body 60.
　電源６５は、ノズル１３とコレクタ５０とに電圧を印加して、ノズルを第１の極性に帯電させ、コレクタ５０を第１の極性と逆極性の第２の極性に帯電させる電圧印加部である。本実施形態では、ノズル１３をマイナス（－）に帯電させ、コレクタ５０をプラス（＋）に帯電させているが、ノズル１３とコレクタ５０との極性は逆であってもよい。本実施形態では、ノズル１３とコレクタ５０とに印加する電圧は３５ｋＶとしている。 The power source 65 is a voltage application unit that applies a voltage to the nozzle 13 and the collector 50 to charge the nozzle to the first polarity, and charges the collector 50 to the second polarity opposite to the first polarity. . In this embodiment, the nozzle 13 is charged to minus (−) and the collector 50 is charged to plus (+). However, the polarity of the nozzle 13 and the collector 50 may be reversed. In the present embodiment, the voltage applied to the nozzle 13 and the collector 50 is 35 kV.
　ノズル１３の先端開口１３ａとコレクタ５０との距離Ｌ２は、セルロース系ポリマーと溶媒の種類、溶液２５における溶媒の質量割合等によって適切な値が異なるが、３０ｍｍ以上３００ｍｍ以下の範囲内が好ましく、本実施形態では１８０ｍｍとしている。この距離Ｌ２が３０ｍｍ以上であることにより、３０ｍｍよりも短い場合に比べて、噴出して形成された紡糸ジェット４５が、コレクタ５０に到達するまでに、自身の電荷による反発でより確実に***するので、細いナノファイバ４６がより確実に得られる。また、このように細く***することで溶媒がより確実に蒸発するから溶媒が残留した不織布となることがより確実に防がれる。また、距離Ｌ２が３００ｍｍ以下であることにより、３００ｍｍを超えて長すぎる場合と比べて、印加する電圧を低く抑えることができるので、異常放電が抑制される。 The distance L2 between the tip opening 13a of the nozzle 13 and the collector 50 varies depending on the type of the cellulose polymer and the solvent, the mass ratio of the solvent in the solution 25, etc., but is preferably in the range of 30 mm to 300 mm. In the embodiment, it is 180 mm. When the distance L2 is 30 mm or more, the spun jet 45 formed by jetting is more reliably split by repulsion due to its own charge before reaching the collector 50, compared to a case where the distance L2 is shorter than 30 mm. Therefore, the thin nanofiber 46 can be obtained more reliably. Moreover, since the solvent evaporates more reliably by splitting in this way, it is more reliably prevented that the non-woven fabric has the solvent remaining. Moreover, since the voltage to apply can be restrained low compared with the case where distance L2 is 300 mm or less and it is too long exceeding 300 mm, abnormal discharge is suppressed.
　ノズル１３とコレクタ５０とに印加する電圧の大きさによって、得られるナノファイバ４６の太さが変わる。ファイバを細く形成する観点では電圧はなるべく低いほうが好ましいが、下げすぎると繊維状にならず玉状になってコレクタ５０上に付着する場合がある。逆に電圧を上げていくとファイバが太くなり、上げ過ぎると装置の絶縁が破れる場合がある。そこで、ノズル１３とコレクタ５０とにかける電圧は、２ｋＶ以上４０ｋＶ以下の範囲内が好ましく、特に好ましくは２０ｋＶ以上３５ｋＶ以下の範囲内である。 The thickness of the obtained nanofiber 46 varies depending on the magnitude of the voltage applied to the nozzle 13 and the collector 50. From the viewpoint of forming a thin fiber, it is preferable that the voltage is as low as possible. However, if it is lowered too much, it may not be in the form of a fiber but may become a ball and adhere to the collector 50 in some cases. Conversely, when the voltage is increased, the fiber becomes thicker, and when it is increased too much, the insulation of the device may be broken. Therefore, the voltage applied to the nozzle 13 and the collector 50 is preferably in the range of 2 kV to 40 kV, particularly preferably in the range of 20 kV to 35 kV.
　セルロース系ポリマーとしては、本実施形態ではセルローストリアセテート（ＴＡＣ）を用いているが、これに限定されず、ＴＡＣ、セルロースジアセテート（ＤＡＣ）、セルロースプロピオネート、セルロースブチレート、セルロースアセテートプロピオネート、ニトロセルロース、エチルセルロース、カルボキシメチルエチルセルロースの少なくともいずれかひとつであればよい。 As the cellulose-based polymer, cellulose triacetate (TAC) is used in the present embodiment, but is not limited thereto. TAC, cellulose diacetate (DAC), cellulose propionate, cellulose butyrate, cellulose acetate propionate , Nitrocellulose, ethylcellulose, or carboxymethylethylcellulose may be used.
　セルロース系ポリマーを溶解する溶媒としては、メタノール、エタノール、イソプロパノール、ブタノール、ベンジルアルコール、アセトン、メチルエチルケトン、シクロヘキサノン、メチルアセテート、エチルアセテート、プロピルアセテート、ブチルアセテート、ギ酸メチル、ギ酸エチル、ヘキサン、シクロヘキサン、ジクロロメタン、クロロホルム、四塩化炭素、ベンゼン、トルエン、キシレン、ジメチルホルムアミド、ＮＭＰ、ジエチルエーテル、ジオキサン、テトラヒドロフラン、１－メトキシ－２－プロパノールなどが挙げられる。これらは、セルロース系ポリマーの種類に応じて単独で使用しても混合して使用してもよい。なお、本実施形態では、溶媒として、ジクロロメタンとＮＭＰとの混合物を用いている。 Solvents for dissolving the cellulose polymer include methanol, ethanol, isopropanol, butanol, benzyl alcohol, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl formate, ethyl formate, hexane, cyclohexane, dichloromethane Chloroform, carbon tetrachloride, benzene, toluene, xylene, dimethylformamide, NMP, diethyl ether, dioxane, tetrahydrofuran, 1-methoxy-2-propanol and the like. These may be used alone or in combination depending on the type of cellulosic polymer. In the present embodiment, a mixture of dichloromethane and NMP is used as the solvent.
　溶媒を単体から構成する場合、すなわち一成分で構成する場合において、溶媒の沸点がおおよそ５０℃以下であると液玉の形成が顕著になる。また、沸点の低い物質は蒸発速度が大きいためにこれを溶媒として用いると溶液は液玉を形成しやすい。このように液玉を形成しやすい場合ほど、本実施形態のように被覆液１６１で覆うことが好ましい。 When the solvent is composed of a single component, that is, when it is composed of one component, the formation of a liquid ball becomes remarkable when the boiling point of the solvent is about 50 ° C. or less. In addition, since a substance having a low boiling point has a high evaporation rate, the solution tends to form a liquid ball when used as a solvent. Thus, it is preferable to cover with the coating liquid 161 like this embodiment, so that it is easy to form a liquid ball.
　次に、上記構成の作用を説明する。ノズル１３と、循環して移動するコレクタ５０とには、電源６５により電圧が印加される。ノズル１３には、貯留容器３０から溶液２５が連続的に供給され、移動するコレクタ５０上には、支持体６０が連続的に供給される。電圧の印加によりプラスに帯電しているコレクタ５０は、先端開口１３ａからマイナスに帯電した状態で出た溶液２５を誘引し、紡糸ジェット４５が形成される。マイナスに帯電している紡糸ジェット４５は、コレクタ５０に向かう間に、自身の電荷による反発でより細い径に***し、支持体６０上にナノファイバ４６として集積する。集積したナノファイバ４６は不織布１２０として支持体６０とともに支持体巻取り部５３に送られる。不織布１２０は、支持体６０と重なった状態で巻芯６１に巻かれる。不織布１２０を有する支持体６０は、ロール形態で巻取り軸５８から取り外された後に、例えば所望のサイズに切断されてシート状にされる。不織布１２０は用途に応じて支持体６０から剥がされて、使用に供される。 Next, the operation of the above configuration will be described. A voltage is applied from the power source 65 to the nozzle 13 and the collector 50 that circulates and moves. The solution 25 is continuously supplied from the storage container 30 to the nozzle 13, and the support body 60 is continuously supplied onto the moving collector 50. The collector 50 that is positively charged by the application of the voltage attracts the solution 25 that has been negatively charged from the tip opening 13a, and a spinning jet 45 is formed. The negatively charged spinning jet 45 splits into a smaller diameter due to repulsion due to its own charge while heading toward the collector 50, and accumulates on the support 60 as nanofibers 46. The integrated nanofiber 46 is sent to the support winding portion 53 together with the support 60 as the nonwoven fabric 120. The nonwoven fabric 120 is wound around the core 61 in a state where it overlaps with the support body 60. The support body 60 having the nonwoven fabric 120 is removed from the winding shaft 58 in a roll form, and then cut into a desired size, for example, into a sheet shape. The nonwoven fabric 120 is peeled off from the support body 60 according to a use, and is used.
　送液スリット１６２からは被覆液１６１が出ており、先端開口１３ａから出ている溶液２５の周囲に連続的に供給される。これにより、先端開口１３ａからの溶液２５の周囲を被覆液１６１が覆われるため、先端開口１３ａから出た溶液２５の表面は乾きにくい。先端開口１３ａからの溶液２５に対して送液スリット１６２からの被覆液１６１が５％以上２０％以下の範囲内とされていることで、先端開口１３ａから出た溶液２５の周囲を被覆液１６１が確実に覆われる。これにより、テイラーコーン４４が確実に形成され、形成されたテイラーコーン４４は表面が乾きにくく、安定して維持される。また、先端開口１３ａから出た溶液２５は被覆液１６１でセルロース系ポリマーの濃度を過度に低下させることもない。このため、テイラーコーン４４から伸びる溶液２５が切れることなく、紡糸ジェット４５が形成され、ナノファイバ４６が製造される。またこのようにテイラーコーン４４が長時間安定するため、ナノファイバ４６からなる不織布が安定して製造される。 The coating liquid 161 comes out from the liquid feeding slit 162 and is continuously supplied around the solution 25 coming out from the tip opening 13a. Thereby, since the coating liquid 161 is covered around the solution 25 from the tip opening 13a, the surface of the solution 25 coming out from the tip opening 13a is difficult to dry. Since the coating liquid 161 from the liquid feeding slit 162 is within a range of 5% or more and 20% or less with respect to the solution 25 from the tip opening 13a, the coating liquid 161 is surrounded around the solution 25 that has come out of the tip opening 13a. Is surely covered. Thereby, the Taylor cone 44 is formed reliably, and the formed Taylor cone 44 is hard to dry and is stably maintained. Further, the solution 25 exiting from the tip opening 13a does not excessively reduce the concentration of the cellulosic polymer by the coating liquid 161. Therefore, the spinning jet 45 is formed without cutting the solution 25 extending from the Taylor cone 44, and the nanofiber 46 is manufactured. Further, since the Taylor cone 44 is stabilized for a long time as described above, the nonwoven fabric made of the nanofibers 46 is stably manufactured.
　被覆液１６１は、溶液２５の溶媒の成分として用いられているものと同じ物質を含むため、先端開口１３ａから出た溶液２５の内部と外部とでは、セルロース系ポリマーの溶解性に差がほとんどない。このため、溶液２５の処方やナノファイバ４６の製造条件について制約が減り、これらの自由度が増す。被覆液１６１は溶液２５よりもセルロース系ポリマーの濃度が低い。このため、先端開口１３ａから出た溶液２５の表面の乾きを抑制してテイラーコーン４４を形成し、形成したテイラーコーン４４の表面の乾きも抑制する。 Since the coating liquid 161 contains the same substance as that used as the solvent component of the solution 25, there is almost no difference in the solubility of the cellulosic polymer between the inside and the outside of the solution 25 exiting from the tip opening 13a. . For this reason, restrictions on the formulation of the solution 25 and the manufacturing conditions of the nanofiber 46 are reduced, and the degree of freedom is increased. The coating liquid 161 has a lower cellulosic polymer concentration than the solution 25. For this reason, drying of the surface of the solution 25 coming out from the tip opening 13a is suppressed to form the Taylor cone 44, and drying of the surface of the formed Taylor cone 44 is also suppressed.
　被覆液１６１の溶液２５に対する体積での流量割合が５％以上２０％以下の範囲内であることにより、先端開口１３ａから出た溶液２５の周囲を被覆液１６１が確実に覆うとともに、溶液２５におけるセルロース系ポリマーの濃度の過度な低下もない。このため、テイラーコーン４４が安定的に維持されて、ナノファイバ４６及び不織布１２０が安定して製造される。 When the ratio of the flow rate of the coating liquid 161 to the solution 25 in the volume is within a range of 5% or more and 20% or less, the coating liquid 161 reliably covers the periphery of the solution 25 that has come out of the tip opening 13a. There is no excessive decrease in the concentration of the cellulosic polymer. For this reason, the Taylor cone 44 is stably maintained, and the nanofiber 46 and the nonwoven fabric 120 are stably manufactured.
　送液管１６０がノズル１３の外周に、ノズル１３と同心に配されていることにより、先端開口１３ａから出た溶液２５は、より確実に周囲全体が被覆液１６１で覆われる。このため、テイラーコーン４４がより確実に形成され、形成されたテイラーコーン４４が長時間安定する。したがって、ナノファイバ４６からなる不織布が安定して製造される。 Since the liquid feeding pipe 160 is arranged on the outer periphery of the nozzle 13 concentrically with the nozzle 13, the entire periphery of the solution 25 coming out from the tip opening 13 a is more reliably covered with the coating liquid 161. For this reason, the Taylor cone 44 is more reliably formed, and the formed Taylor cone 44 is stabilized for a long time. Therefore, the nonwoven fabric which consists of the nanofiber 46 is manufactured stably.
　送液管１６０がノズル１３の先端開口１３ａよりも突出するように配されていることにより、形成されたテイラーコーン４４はより確実に被覆液１６１で覆われて長時間安定する。このため、ナノファイバ４６からなる不織布が安定して製造される。 Since the liquid feeding pipe 160 is arranged so as to protrude from the tip opening 13a of the nozzle 13, the formed Taylor cone 44 is more reliably covered with the coating liquid 161 and stabilized for a long time. For this reason, the nonwoven fabric which consists of nanofiber 46 is manufactured stably.
　以上のように、被覆液１６１が先端開口１３ａから出た溶液２５及びこの溶液２５から形成されたテイラーコーン４４を覆うため、溶液２５の溶媒の蒸発が低く抑えられる。これにより、テイラーコーン４４の表面が固くなることがなく、液玉の発生が抑えられる。したがって、液玉の発生に起因して不均一な太さのナノファイバ４６が形成される問題や、液玉の落下による欠陥製品の発生の問題などが解消される。このように、蒸発しやすい溶媒が用いられているセルロース系ポリマー溶液であっても電界紡糸が安定的に行われる。 As described above, since the coating liquid 161 covers the solution 25 coming out of the tip opening 13a and the Taylor cone 44 formed from the solution 25, the evaporation of the solvent of the solution 25 can be kept low. Thereby, the surface of the Taylor cone 44 does not become hard, and generation | occurrence | production of a liquid ball is suppressed. Therefore, the problem that the nanofibers 46 having a non-uniform thickness are formed due to the generation of liquid balls, the problem of generation of defective products due to the drop of liquid balls, and the like are solved. Thus, electrospinning is stably performed even with a cellulose polymer solution in which a solvent that easily evaporates is used.
　ナノファイバ４６は、バイオフィルタ、センサ、燃料電池電極材、精密フィルタ、電子ペーパ等の製造に利用することができる可能性がある。また、比較的低い温度で使用されるヒートパイプのウイックとしても伝達熱量が大きく、たとえば地中の熱を利用したエコシステムなどへの利用の可能性がある。また、肌ざわりのよい美容用パック素材として使用することができる可能性がある。 There is a possibility that the nanofiber 46 can be used for the production of biofilters, sensors, fuel cell electrode materials, precision filters, electronic paper, and the like. In addition, a heat pipe wick that is used at a relatively low temperature has a large amount of heat to be transferred, and may be used for an ecosystem that uses underground heat, for example. Moreover, there is a possibility that it can be used as a beauty pack material with a good texture.
　ナノファイバ４６を平滑な表面の不織布１２０として得るために、コレクタ５０は表面が平滑なものとしているが、コレクタ５０の形状は限定されない。例えば、コレクタ５０に代えて円筒状の回転体を用いてもよい。この場合には、回転体の表面に筒状の不織布がナノファイバ４６から形成されるため、製造後に回転体から筒状の不織布を抜き取り、所望の大きさ及び形状にカットして所定の不織布製品とすることができる。円筒状の回転体を用いる場合には、不織布を連続的には製造できないものの、均質な不織布製品が作りやすい。このため、細胞培養用足場や医療用途などへの応用が容易になる可能性がある。また回転体の回転数を高くすることによって、ナノファイバの配向度を高めることができ、異方性のある製品を得ることができる。 In order to obtain the nanofiber 46 as the smooth nonwoven fabric 120, the collector 50 has a smooth surface, but the shape of the collector 50 is not limited. For example, a cylindrical rotating body may be used instead of the collector 50. In this case, since the cylindrical nonwoven fabric is formed from the nanofibers 46 on the surface of the rotating body, the cylindrical nonwoven fabric is extracted from the rotating body after manufacturing and cut into a desired size and shape to obtain a predetermined nonwoven fabric product. It can be. When a cylindrical rotating body is used, a non-woven fabric cannot be continuously produced, but a uniform non-woven fabric product is easy to make. For this reason, there is a possibility that application to cell culture scaffolds, medical uses, and the like becomes easy. Further, by increasing the number of rotations of the rotator, the degree of orientation of the nanofiber can be increased, and an anisotropic product can be obtained.
　上記第１実施形態では、ノズル１３の先端開口１３ａに対して、送液管１６０の先端１６０ａを突出させて、テイラーコーン４４を送液管１６０で覆うようにしているが、ノズルと送液管１６０との先端の位置関係はこれに限られない。例えば、図３に示す第２実施形態のように、ノズル１３の先端１３ｃに合わせて送液管１７０の先端１７０ａを位置させてもよい。この場合には、第１実施形態のように、ノズル１３の先端１３ｃが送液管１７０の先端部１７０ｂ内に隠れることがないため、先端１３ｃのクリーニングが容易である。なお、各実施形態において、同じ構成部材には同一符号を付して重複した説明を省略している。 In the first embodiment, the tip 160a of the liquid feeding pipe 160 protrudes from the tip opening 13a of the nozzle 13 so that the Taylor cone 44 is covered with the liquid feeding pipe 160. However, the nozzle and the liquid feeding pipe are used. The positional relationship of the tip with 160 is not limited to this. For example, as in the second embodiment shown in FIG. 3, the tip 170 a of the liquid feeding tube 170 may be positioned in accordance with the tip 13 c of the nozzle 13. In this case, unlike the first embodiment, the tip 13c of the nozzle 13 is not hidden in the tip 170b of the liquid feeding tube 170, so that the tip 13c can be easily cleaned. In each embodiment, the same constituent members are denoted by the same reference numerals, and redundant description is omitted.
　図４に示すように、本発明の第３実施形態は、第２実施形態の送液管１７０の先端部１７０ｂに、ガイド管１７５を筒心方向に移動自在に取り付けたものである。この第３実施形態の場合には、ガイド管１７５を下ろしたガイド位置（図４参照）では、ガイド管１７５及び送液管１７０によって、送液スリット１６２からの被覆液１６１がテイラーコーン４４を覆うため、テイラーコーン４４の表面の乾きを確実に抑制する。また、クリーニングの際には、ガイド管１７５をガイド位置から上方にスライドさせて退避位置にすることにより、ノズル１３の先端１３ｃを露出させることができる。このため、ノズル１３の先端開口１３ａを確実にクリーニングすることができる。ガイド管１７５は、図示省略のバネなどにより先端に向けて突出するように付勢してもよいし、同じく図示省略のクリック機構により突出位置と退避位置とに位置決め可能にしてもよい。 As shown in FIG. 4, in the third embodiment of the present invention, a guide tube 175 is movably attached to the distal end portion 170b of the liquid feeding tube 170 of the second embodiment. In the case of the third embodiment, the coating liquid 161 from the liquid feeding slit 162 covers the Taylor cone 44 by the guide pipe 175 and the liquid feeding pipe 170 at the guide position (see FIG. 4) where the guide pipe 175 is lowered. Therefore, drying of the surface of the Taylor cone 44 is reliably suppressed. In cleaning, the tip 13c of the nozzle 13 can be exposed by sliding the guide tube 175 upward from the guide position to the retracted position. For this reason, the tip opening 13a of the nozzle 13 can be reliably cleaned. The guide tube 175 may be urged so as to protrude toward the tip by a spring (not shown) or the like, and may be positioned at a protruding position and a retracted position by a click mechanism (not shown).
　上記の送液管１６０及び送液管１７０は、内径及び外径が均一な円管であるが、図５に示す第４実施形態の送液管１８０のように内径及び外径が被覆液１６１及び溶液２５の流れ方向において変化している円管であってもよい。送液管１８０は、内径及び外径が被覆液１６１及び溶液２５の流れ方向において漸減した先細形状の先細部１８０ｃと、内径及び外径が均一な先端部１８０ｂとを有する。送液管１８０の先端部１８０ｂは、この例では先端１８０ａがノズル１３の先端１３ｃよりも突出しているが、第２実施形態の送液管１７０のように先端１３ｃと面一に位置してもよい。 The liquid feeding pipe 160 and the liquid feeding pipe 170 are circular pipes having a uniform inner diameter and outer diameter, but the inner diameter and the outer diameter are coating liquid 161 like the liquid feeding pipe 180 of the fourth embodiment shown in FIG. And the circular pipe which is changing in the flow direction of solution 25 may be sufficient. The liquid feeding pipe 180 has a tapered tapered portion 180c having an inner diameter and an outer diameter that gradually decrease in the flow direction of the coating liquid 161 and the solution 25, and a tip portion 180b having a uniform inner diameter and outer diameter. In this example, the distal end portion 180b of the liquid feeding pipe 180 protrudes from the distal end 13c of the nozzle 13. However, the distal end section 180b may be flush with the distal end 13c as in the liquid feeding pipe 170 of the second embodiment. Good.
　図６に示す第５実施形態の送液管１９０は、被覆液１６１の流路が、ノズル１３の周方向で４つに分割されたものである。このように、被覆液１６１の流路はノズル１３の周方向において複数に分割されていてもよい。この例において流路を仕切る仕切り部材１９０ｃは、ノズル１３を保持する保持機能ももつ。送液管１９０の先端部１９０ｂは、この例では先端１９０ａがノズル１３の先端１３ｃよりも突出しているが、第２実施形態の送液管１７０のように先端１３ｃと面一に位置してもよい。 In the liquid feeding pipe 190 of the fifth embodiment shown in FIG. 6, the flow path of the coating liquid 161 is divided into four in the circumferential direction of the nozzle 13. As described above, the flow path of the coating liquid 161 may be divided into a plurality of parts in the circumferential direction of the nozzle 13. In this example, the partition member 190 c that partitions the flow path also has a holding function for holding the nozzle 13. In this example, the tip 190b of the liquid feeding tube 190 protrudes from the tip 13c of the nozzle 13. However, the tip 190b may be flush with the tip 13c as in the liquid feeding tube 170 of the second embodiment. Good.
　図７に示す第６実施形態の送液管１９５は、六角管とされている。このように、送液管は円管には限られず多角管であってもよい。送液管１９５の先端部１９５ｂは、その先端１９５ａがノズル１３の先端１３ｃよりも突出しているが、第２実施形態の送液管１７０のように先端１３ｃと面一に位置してもよい。 The liquid feeding pipe 195 of the sixth embodiment shown in FIG. 7 is a hexagonal pipe. Thus, the liquid feeding pipe is not limited to a circular pipe and may be a polygonal pipe. The tip 195b of the liquid feeding tube 195 has its tip 195a protruding from the tip 13c of the nozzle 13, but may be positioned flush with the tip 13c as in the liquid feeding tube 170 of the second embodiment.
　上記各実施形態では、ノズル１３を１本のみ用いているが、ノズル１３は複数用いてもよい。複数用いる場合には、支持体６０の移動方向に直交する方向に複数のノズル１３を離間して設けることが好ましい。また、支持体６０の移動方向、及び移動方向に直交する方向でノズル１３をマトリックスに配置してもよい。ノズル１３を複数用いることで、得られる不織布１２０が大面積化され、製造効率が上がる。また、ノズル１３の本数が増加してノズル１３からの溶液の総量が増加する場合には、紡糸室１１内に図示省略の溶媒回収部を設けることが好ましい。 In each of the above embodiments, only one nozzle 13 is used, but a plurality of nozzles 13 may be used. When a plurality of nozzles 13 are used, it is preferable that the plurality of nozzles 13 be provided apart from each other in a direction orthogonal to the moving direction of the support 60. Further, the nozzles 13 may be arranged in a matrix in the moving direction of the support 60 and in a direction orthogonal to the moving direction. By using a plurality of nozzles 13, the resulting non-woven fabric 120 is increased in area and manufacturing efficiency is increased. When the number of nozzles 13 increases and the total amount of solution from the nozzles 13 increases, it is preferable to provide a solvent recovery unit (not shown) in the spinning chamber 11.
　ナノファイバ製造装置１５０により、ナノファイバ４６を不織布１２０として製造した。溶液２５の流量を４ｃｍ３／時、送液スリット１６２からの被覆液１６１の流量を溶液２５の流量よりも小さい０．５ｃｍ３／時とした。溶液２５におけるセルロース系ポリマーとしてのＴＡＣの濃度Ｃは４質量％、被覆液１６１におけるセルロース系ポリマーとしてのＴＡＣの濃度は３質量％とした。なお、溶液２５の組成、被覆液１６１の組成は前述の通りである。また、用いた送液管１６０の素材、サイズ、突出量Ｌ１、コレクタ５０及び支持体６０の素材及び移動速度、印加した電圧の値等も前述の通りである。 The nanofiber 46 was manufactured as the nonwoven fabric 120 by the nanofiber manufacturing apparatus 150. The flow rate of the solution 25 was 4 cm 3 / hour, and the flow rate of the coating liquid 161 from the liquid feeding slit 162 was 0.5 cm 3 / hour, which was smaller than the flow rate of the solution 25. The concentration C of TAC as the cellulose polymer in the solution 25 was 4 mass%, and the concentration of TAC as the cellulose polymer in the coating liquid 161 was 3 mass%. The composition of the solution 25 and the composition of the coating liquid 161 are as described above. Further, the material and size of the liquid feeding pipe 160 used, the protruding amount L1, the material and moving speed of the collector 50 and the support 60, the value of the applied voltage, and the like are as described above.
　この実施例では、連続的にナノファイバ４６を製造することができ、長尺の不織布１２０が得られた。 In this example, the nanofibers 46 could be manufactured continuously, and a long nonwoven fabric 120 was obtained.
　［比較例１］
　送液管１６０から被覆液１６１を供給しなかった以外は、実施例１と同じ条件とした。この比較例１においては、製造開始によりテイラーコーン４４は形成されたが、紡糸ジェットの形成開始から約５分でテイラーコーン４４の形状が崩れて液玉が形成されてしまい、紡糸ジェット４５の形成が中断した。その数秒後に液玉の側部が破れて糸が噴き出したがまたすぐに紡糸ジェット４５の形成が中断した。以降、紡糸ジェット４５は形成されず、ナノファイバ４６を製造することができなかった。 [Comparative Example 1]
The conditions were the same as in Example 1 except that the coating liquid 161 was not supplied from the liquid feeding pipe 160. In Comparative Example 1, the Taylor cone 44 was formed at the start of production. However, the shape of the Taylor cone 44 collapsed and a liquid ball was formed in about 5 minutes from the start of the formation of the spinning jet. Was interrupted. Several seconds later, the side of the liquid ball was torn and the yarn spouted out, but the formation of the spinning jet 45 was immediately interrupted. Thereafter, the spinning jet 45 was not formed, and the nanofiber 46 could not be manufactured.
　［比較例２］
　送液スリット１６２からの被覆液１６１の流量を２ｃｍ３／時とした以外は、実施例１と同じ条件とした。この比較例２においては、製造開始によりテイラーコーン４４は形成されたが、テイラーコーン４４の形状が安定せず、ナノファイバ４６は断続的にしか製造されなかった。 [Comparative Example 2]
The conditions were the same as in Example 1 except that the flow rate of the coating liquid 161 from the liquid feeding slit 162 was 2 cm 3 / hour. In Comparative Example 2, the Taylor cone 44 was formed at the start of production, but the shape of the Taylor cone 44 was not stable, and the nanofiber 46 was produced only intermittently.
　［比較例３］
　実施例１の被覆液１６１を、ＴＡＣの濃度が８質量％の被覆液に代えた他は、実施例１と同じ条件とした。この比較例３においては、液玉が形成され、紡糸ジェット４５の形成は断続的であった。液玉の下部と側部とからそれぞれ糸が噴き出し、そのまま製造を続けて行うにつれて液玉が不規則な形状で下方に成長し、製造開始から１０分程度でコレクタ５０上の支持体６０に落下した。 [Comparative Example 3]
The same conditions as in Example 1 were used except that the coating liquid 161 in Example 1 was replaced with a coating liquid having a TAC concentration of 8% by mass. In Comparative Example 3, a liquid ball was formed, and the formation of the spinning jet 45 was intermittent. Yarns spout from the lower part and side part of the liquid ball, and as production continues, the liquid ball grows downward in an irregular shape and falls on the support 60 on the collector 50 in about 10 minutes from the start of production. did.
１３　　ノズル
１３ａ　先端開口
１５　　集積部
２５　　溶液
４６　　ナノファイバ
５０　　コレクタ
６５　　電源
１２０　不織布
１５０　ナノファイバ製造装置
１５４　被覆液供給部
１６０　送液管
１６１　被覆液 13 Nozzle 13a End opening 15 Accumulation unit 25 Solution 46 Nanofiber 50 Collector 65 Power source 120 Non-woven fabric 150 Nanofiber production device 154 Coating liquid supply unit 160 Liquid supply pipe 161 Coating liquid

Claims (9)

  1. 　セルロース系ポリマーが溶媒に溶解し、第１の極性に帯電された状態の溶液をノズルから出し、
    　前記ノズルの前記溶液が出る先端に、前記溶媒の成分と同じ物質を含み前記溶液よりもセルロース系ポリマーの濃度が低い液を前記溶液に対して５％以上２０％以下の範囲内の体積での流量割合で供給して、前記先端から出た前記溶液の周囲を前記液で覆い、
    　前記第１の極性と逆極性の第２の極性に帯電されたコレクタにより、前記ノズルから出た前記溶液を誘引しナノファイバとして捕集することを特徴とするナノファイバ製造方法。     The cellulosic polymer is dissolved in the solvent, and the solution charged in the first polarity is discharged from the nozzle,
    At the tip of the nozzle where the solution exits, a liquid containing the same substance as the solvent component and having a lower concentration of cellulosic polymer than the solution is in a volume within a range of 5% to 20% with respect to the solution. Supply at a flow rate ratio, and cover the solution around the tip with the liquid,
    A method for producing a nanofiber, wherein the solution charged from the nozzle is attracted and collected as a nanofiber by a collector charged to a second polarity opposite to the first polarity.
  2. 　前記ノズルと、前記ノズルの外周に隙間をもって前記ノズルと同心で配された送液管と、の間から前記液を出すことにより、前記液を供給する請求項１に記載のナノファイバ製造方法。 The method for producing a nanofiber according to claim 1, wherein the liquid is supplied by discharging the liquid from between the nozzle and a liquid supply pipe arranged concentrically with the nozzle with a gap around the outer periphery of the nozzle.
  3. 　前記送液管の前記液が出る先端は、前記ノズルの先端よりも突出している請求項２に記載のナノファイバ製造方法。 The nanofiber manufacturing method according to claim 2, wherein a tip of the liquid feeding tube from which the liquid comes out protrudes from a tip of the nozzle.
  4. 　前記セルロース系ポリマーは、セルローストリアセテート、セルロースジアセテート、セルロースプロピオネート、セルロースブチレート、セルロースアセテートプロピオネート、ニトロセルロース、エチルセルロース、カルボキシメチルエチルセルロースの少なくともいずれかひとつである請求項１ないし３のいずれか１項に記載のナノファイバ製造方法。 The cellulosic polymer is at least one of cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, nitrocellulose, ethylcellulose, and carboxymethylethylcellulose. The nanofiber manufacturing method according to claim 1.
  5. 　セルロース系ポリマーが溶媒に溶解した溶液を出すノズルと、
    　前記ノズルの前記溶液が出る先端に、前記溶媒の成分と同じ物質を含み前記溶液よりもセルロース系ポリマーの濃度が低い液を前記溶液に対して５％以上２０％以下の範囲内の体積での流量割合で供給して、前記先端から出た前記溶液の周囲を前記液で覆う供給部と、
    　前記ノズルから出た前記溶液を誘引し、ナノファイバとして捕集するコレクタと、
    　前記ノズルから出る前記溶液と前記コレクタとに電圧を印加することにより前記溶液と前記コレクタとを逆極性に帯電させる電圧印加部と、
    　を備えることを特徴とするナノファイバ製造装置。     A nozzle for dispensing a solution in which a cellulosic polymer is dissolved in a solvent;
    At the tip of the nozzle where the solution exits, a liquid containing the same substance as the solvent component and having a lower concentration of cellulosic polymer than the solution is in a volume within a range of 5% to 20% with respect to the solution. Supplying at a flow rate ratio and covering the periphery of the solution from the tip with the liquid;
    A collector that attracts the solution from the nozzle and collects it as nanofibers;
    A voltage application unit that charges the solution and the collector in opposite polarities by applying a voltage to the solution and the collector that exit from the nozzle;
    An apparatus for producing nanofiber, comprising:
  6. 　前記ノズルの外周に隙間をもって前記ノズルと同心で配され、前記ノズルの外周との間から前記液を出して供給する送液管、をさらに備える請求項５に記載のナノファイバ製造装置。 6. The nanofiber manufacturing apparatus according to claim 5, further comprising a liquid feeding pipe arranged concentrically with the nozzle with a gap around the nozzle, and supplying and supplying the liquid from between the nozzle and the outer circumference.
  7. 　前記送液管の前記液が出る先端は、前記ノズルの先端よりも突出している請求項６に記載のナノファイバ製造装置。 The nanofiber manufacturing apparatus according to claim 6, wherein a tip of the liquid feeding tube from which the liquid comes out protrudes from a tip of the nozzle.
  8. 　前記セルロース系ポリマーは、セルローストリアセテート、セルロースジアセテート、セルロースプロピオネート、セルロースブチレート、セルロースアセテートプロピオネート、ニトロセルロース、エチルセルロース、カルボキシメチルエチルセルロースの少なくともいずれかひとつであることを特徴とする請求項５ないし７のいずれか１項に記載のナノファイバ製造装置。 The cellulosic polymer is at least one of cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, nitrocellulose, ethylcellulose, and carboxymethylethylcellulose. The nanofiber manufacturing apparatus according to any one of 5 to 7.
  9. 　セルロース系ポリマーが溶媒に溶解し、第１の極性に帯電された状態の溶液をノズルから出し、
    　前記ノズルの前記溶液が出る先端に、前記溶媒の成分と同じ物質を含み前記溶液よりもセルロース系ポリマーの濃度が低い液を前記溶液に対して５％以上２０％以下の範囲内の体積での流量割合で供給して、前記先端から出た前記溶液の周囲を前記液で覆い、
    　前記第１の極性と逆極性の第２の極性に帯電された移動するコレクタにより、前記ノズルから出た前記溶液を誘引して前記コレクタ上に配された支持体にナノファイバとして捕集し、
    　捕集した前記ナノファイバを前記支持体上で集積させることにより不織布とすることを特徴とする不織布製造方法。     The cellulosic polymer is dissolved in the solvent, and the solution charged in the first polarity is discharged from the nozzle,
    At the tip of the nozzle where the solution exits, a liquid containing the same substance as the solvent component and having a lower concentration of cellulosic polymer than the solution is in a volume within a range of 5% to 20% with respect to the solution. Supply at a flow rate ratio, and cover the solution around the tip with the liquid,
    The moving collector charged to a second polarity opposite to the first polarity attracts the solution from the nozzle and collects it as a nanofiber on a support disposed on the collector,
    A method for producing a nonwoven fabric, comprising collecting the nanofibers collected on the support to form a nonwoven fabric.
PCT/JP2015/070371 2014-09-04 2015-07-16 Process and device for producing nanofiber, and process for producing nonwoven fabric WO2016035458A1 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017158879A1 (en) * 2016-03-16 2017-09-21 株式会社 東芝 Nozzle head and electrospinning device
WO2018147068A1 (en) * 2017-02-13 2018-08-16 富士フイルム株式会社 Sheet and method for producing sheet
CN111918993A (en) * 2018-03-28 2020-11-10 富士胶片株式会社 Nonwoven fabric, fiber forming method, and nonwoven fabric manufacturing method

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020184136A1 (en) * 2019-03-12 2020-09-17 富士フイルム株式会社 Nonwoven cloth, and method for manufacturing nonwoven cloth

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008138297A (en) * 2006-11-30 2008-06-19 Fujifilm Corp Material and method for eliminating harmful substance
JP2009035854A (en) * 2007-07-11 2009-02-19 Panasonic Corp Method and apparatus for manufacturing fine polymer
JP2010236133A (en) * 2009-03-31 2010-10-21 National Institute Of Advanced Industrial Science & Technology Apparatus for producing nanofiber by electrospinning method using double-pipe nozzle and nanofiber production method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5637479B2 (en) * 2010-12-06 2014-12-10 光弘 高橋 Nanofiber manufacturing equipment

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008138297A (en) * 2006-11-30 2008-06-19 Fujifilm Corp Material and method for eliminating harmful substance
JP2009035854A (en) * 2007-07-11 2009-02-19 Panasonic Corp Method and apparatus for manufacturing fine polymer
JP2010236133A (en) * 2009-03-31 2010-10-21 National Institute Of Advanced Industrial Science & Technology Apparatus for producing nanofiber by electrospinning method using double-pipe nozzle and nanofiber production method

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017158879A1 (en) * 2016-03-16 2017-09-21 株式会社 東芝 Nozzle head and electrospinning device
US10745826B2 (en) 2016-03-16 2020-08-18 Kabushiki Kaisha Toshiba Nozzle head and electrospinning apparatus
WO2018147068A1 (en) * 2017-02-13 2018-08-16 富士フイルム株式会社 Sheet and method for producing sheet
JP2018131692A (en) * 2017-02-13 2018-08-23 富士フイルム株式会社 Sheet and sheet production method
CN110291241A (en) * 2017-02-13 2019-09-27 富士胶片株式会社 Sheet material and sheet manufacturing method
CN110291241B (en) * 2017-02-13 2022-02-08 富士胶片株式会社 Sheet and sheet manufacturing method
CN111918993A (en) * 2018-03-28 2020-11-10 富士胶片株式会社 Nonwoven fabric, fiber forming method, and nonwoven fabric manufacturing method
CN111918993B (en) * 2018-03-28 2022-07-26 富士胶片株式会社 Nonwoven fabric, fiber forming method, and nonwoven fabric manufacturing method

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